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zshcompsys (1)

Name

zshcompsys - zsh completion system

Synopsis

Please see following description for synopsis

Description

ZSHCOMPSYS(1)               General Commands Manual              ZSHCOMPSYS(1)



NAME
       zshcompsys - zsh completion system

DESCRIPTION
       This describes the shell code for the `new' completion system, referred
       to as compsys.  It is written in shell functions based on the  features
       described in zshcompwid(1).

       The features are contextual, sensitive to the point at which completion
       is started.  Many completions are already provided.  For this reason, a
       user  can perform a great many tasks without knowing any details beyond
       how to initialize the system, which is described below  in  INITIALIZA-
       TION.

       The context that decides what completion is to be performed may be
       o      an  argument  or option position: these describe the position on
              the command line at which completion is requested.  For  example
              `first  argument  to  rmdir,  the  word  being completed names a
              directory';


       o      a special context, denoting an element in  the  shell's  syntax.
              For  example  `a  word  in  command  position' or `an array sub-
              script'.


       A full context specification  contains  other  elements,  as  we  shall
       describe.

       Besides  commands  names and contexts, the system employs two more con-
       cepts, styles and tags.  These provide ways for the user  to  configure
       the system's behaviour.

       Tags  play  a dual role.  They serve as a classification system for the
       matches, typically indicating a class of object that the user may  need
       to  distinguish.  For example, when completing arguments of the ls com-
       mand the user may prefer to try files before directories,  so  both  of
       these are tags.  They also appear as the rightmost element in a context
       specification.

       Styles modify various operations of the completion system, such as out-
       put formatting, but also what kinds of completers are used (and in what
       order), or which tags are examined.  Styles may  accept  arguments  and
       are  manipulated  using  the  zstyle  command  described in see zshmod-
       ules(1).

       In summary, tags describe what the completion objects  are,  and  style
       how they are to be completed.  At various points of execution, the com-
       pletion system checks what styles and/or tags are defined for the  cur-
       rent  context, and uses that to modify its behavior.  The full descrip-
       tion of context handling, which determines how tags and other  elements
       of the context influence the behaviour of styles, is described below in
       COMPLETION SYSTEM CONFIGURATION.

       When a completion is requested, a dispatcher function  is  called;  see
       the  description  of  _main_complete  in  the list of control functions
       below. This dispatcher decides which function should be called to  pro-
       duce the completions, and calls it. The result is passed to one or more
       completers, functions that implement individual completion  strategies:
       simple  completion, error correction, completion with error correction,
       menu selection, etc.

       More generally, the shell functions contained in the completion  system
       are of two types:
       o      those beginning `comp' are to be called directly; there are only
              a few of these;


       o      those beginning `_' are called  by  the  completion  code.   The
              shell  functions  of this set, which implement completion behav-
              iour and may be bound to keystrokes, are referred  to  as  `wid-
              gets'.  These proliferate as new completions are required.


INITIALIZATION
       If the system was installed completely, it should be enough to call the
       shell function compinit from your initialization  file;  see  the  next
       section.   However,  the  function  compinstall can be run by a user to
       configure various aspects of the completion system.

       Usually, compinstall will insert code into .zshrc, although if that  is
       not  writable  it will save it in another file and tell you that file's
       location.  Note that it is up to you to make sure that the lines  added
       to  .zshrc are actually run; you may, for example, need to move them to
       an earlier place in the file if .zshrc usually returns early.  So  long
       as you keep them all together (including the comment lines at the start
       and finish), you can rerun compinstall and it will correctly locate and
       modify  these lines.  Note, however, that any code you add to this sec-
       tion by hand is likely to be lost if you  rerun  compinstall,  although
       lines using the command `zstyle' should be gracefully handled.

       The  new  code  will  take effect next time you start the shell, or run
       .zshrc by hand; there is also an option to make them take effect  imme-
       diately.   However,  if  compinstall  has removed definitions, you will
       need to restart the shell to see the changes.

       To run compinstall you will need to make sure it is in a directory men-
       tioned in your fpath parameter, which should already be the case if zsh
       was properly configured as long as your startup files do not remove the
       appropriate  directories  from  fpath.   Then  it  must  be  autoloaded
       (`autoload -U compinstall' is recommended).  You can abort the  instal-
       lation any time you are being prompted for information, and your .zshrc
       will not be altered at all; changes only take place right at  the  end,
       where you are specifically asked for confirmation.

   Use of compinit
       This section describes the use of compinit to initialize completion for
       the current session when called directly; if you have  run  compinstall
       it will be called automatically from your .zshrc.

       To  initialize  the system, the function compinit should be in a direc-
       tory mentioned  in  the  fpath  parameter,  and  should  be  autoloaded
       (`autoload  -U  compinit'  is  recommended),  and  then  run  simply as
       `compinit'.  This will define a few utility functions, arrange for  all
       the necessary shell functions to be autoloaded, and will then re-define
       all widgets that do completion to use the new system.  If you  use  the
       menu-select  widget,  which  is  part  of  the zsh/complist module, you
       should make sure that that module is loaded before the call to compinit
       so  that  that  widget  is  also re-defined.  If completion styles (see
       below) are set up  to  perform  expansion  as  well  as  completion  by
       default,  and the TAB key is bound to expand-or-complete, compinit will
       rebind it to complete-word; this is necessary to use the  correct  form
       of expansion.

       Should  you need to use the original completion commands, you can still
       bind keys to the old widgets by putting a `.' in front  of  the  widget
       name, e.g. `.expand-or-complete'.

       To speed up the running of compinit, it can be made to produce a dumped
       configuration that will be read in on future invocations; this  is  the
       default,  but can be turned off by calling compinit with the option -D.
       The dumped file is .zcompdump in the  same  directory  as  the  startup
       files  (i.e.  $ZDOTDIR  or $HOME); alternatively, an explicit file name
       can be given  by  `compinit  -d  dumpfile'.   The  next  invocation  of
       compinit  will  read  the dumped file instead of performing a full ini-
       tialization.

       If the number of completion files changes, compinit will recognise this
       and produce a new dump file.  However, if the name of a function or the
       arguments in the first line of a #compdef function (as described below)
       change,  it is easiest to delete the dump file by hand so that compinit
       will re-create it the next time it is run.  The check performed to  see
       if  there are new functions can be omitted by giving the option -C.  In
       this case the dump file  will  only  be  created  if  there  isn't  one
       already.

       The  dumping  is  actually  done by another function, compdump, but you
       will only need to run this yourself if  you  change  the  configuration
       (e.g.  using  compdef)  and then want to dump the new one.  The name of
       the old dumped file will be remembered for this purpose.

       If the parameter _compdir is set, compinit uses it as a directory where
       completion  functions  can be found; this is only necessary if they are
       not already in the function search path.

       For security reasons compinit also  checks  if  the  completion  system
       would  use  files not owned by root or by the current user, or files in
       directories that are world- or group-writable or that are not owned  by
       root  or  by the current user.  If such files or directories are found,
       compinit will ask if the completion system should really be  used.   To
       avoid  these tests and make all files found be used without asking, use
       the option -u, and to make compinit silently ignore all insecure  files
       and  directories  use  the  option  -i.  This security check is skipped
       entirely when the -C option is given.

       The security check can be retried at any time by running  the  function
       compaudit.   This  is  the  same check used by compinit, but when it is
       executed directly any changes to fpath are made local to  the  function
       so they do not persist.  The directories to be checked may be passed as
       arguments; if none are given, compaudit uses fpath and _compdir to find
       completion  system  directories, adding missing ones to fpath as neces-
       sary.  To force a check of exactly the directories currently  named  in
       fpath,  set  _compdir  to  an  empty string before calling compaudit or
       compinit.

       The function bashcompinit provides compatibility with  bash's  program-
       mable  completion system.  When run it will define the functions, comp-
       gen and complete which correspond to the bash builtins  with  the  same
       names.   It  will then be possible to use completion specifications and
       functions written for bash.

   Autoloaded files
       The convention for autoloaded functions used in completion is that they
       start with an underscore; as already mentioned, the fpath/FPATH parame-
       ter must contain the directory in which they are stored.   If  zsh  was
       properly  installed on your system, then fpath/FPATH automatically con-
       tains the required directories for the standard functions.

       For incomplete installations, if compinit does not  find  enough  files
       beginning with an underscore (fewer than twenty) in the search path, it
       will try to find more by adding the directory _compdir  to  the  search
       path.  If that directory has a subdirectory named Base, all subdirecto-
       ries will be added to the path.  Furthermore, if the subdirectory  Base
       has  a subdirectory named Core, compinit will add all subdirectories of
       the subdirectories to the path: this allows the functions to be in  the
       same format as in the zsh source distribution.

       When  compinit  is  run,  it  searches  all  such  files accessible via
       fpath/FPATH and reads the first line of each of them.  This line should
       contain  one  of the tags described below.  Files whose first line does
       not start with one of these tags are not considered to be part  of  the
       completion system and will not be treated specially.

       The tags are:

       #compdef name ... [ -{p|P} pattern ... [ -N name ... ] ]
              The  file  will be made autoloadable and the function defined in
              it will be called when completing names, each of which is either
              the name of a command whose arguments are to be completed or one
              of a number of special contexts in the form -context-  described
              below.

              Each  name may also be of the form `cmd=service'.  When complet-
              ing the command cmd, the function typically behaves  as  if  the
              command   (or  special  context)  service  was  being  completed
              instead.  This provides a way of altering the behaviour of func-
              tions that can perform many different completions.  It is imple-
              mented by setting the parameter $service when calling the  func-
              tion;  the  function may choose to interpret this how it wishes,
              and simpler functions will probably ignore it.

              If the #compdef line contains one of the options -p or  -P,  the
              words  following are taken to be patterns.  The function will be
              called when completion is attempted for  a  command  or  context
              that  matches  one  of  the patterns.  The options -p and -P are
              used to specify patterns to be tried before or after other  com-
              pletions  respectively.  Hence -P may be used to specify default
              actions.

              The option -N is used after a list following -p or -P; it speci-
              fies that remaining words no longer define patterns.  It is pos-
              sible to toggle between the three options as many times as  nec-
              essary.

       #compdef -k style key-sequence ...
              This  option  creates  a widget behaving like the builtin widget
              style and binds it to the  given  key-sequences,  if  any.   The
              style  must  be  one of the builtin widgets that perform comple-
              tion, namely complete-word, delete-char-or-list,  expand-or-com-
              plete,  expand-or-complete-prefix,  list-choices, menu-complete,
              menu-expand-or-complete,  or  reverse-menu-complete.    If   the
              zsh/complist  module  is  loaded  (see zshmodules(1)) the widget
              menu-select is also available.

              When one of the key-sequences is typed, the function in the file
              will  be  invoked to generate the matches.  Note that a key will
              not be re-bound if it already was (that is, was bound  to  some-
              thing  other  than  undefined-key).   The widget created has the
              same name as the file and can be bound to any other  keys  using
              bindkey as usual.

       #compdef -K widget-name style key-sequence [ name style seq ... ]
              This is similar to -k except that only one key-sequence argument
              may be given for each  widget-name  style  pair.   However,  the
              entire  set  of three arguments may be repeated with a different
              set of arguments.  Note in particular that the widget-name  must
              be  distinct  in  each  set.  If it does not begin with `_' this
              will be added.  The widget-name should not clash with  the  name
              of  any existing widget: names based on the name of the function
              are most useful.  For example,

                     #compdef -K _foo_complete complete-word "^X^C" \
                       _foo_list list-choices "^X^D"

              (all on one line) defines a widget _foo_complete for completion,
              bound  to  `^X^C',  and a widget _foo_list for listing, bound to
              `^X^D'.

       #autoload [ options ]
              Functions with the #autoload tag are marked for autoloading  but
              are  not  otherwise treated specially.  Typically they are to be
              called from within one of the completion functions.  Any options
              supplied  will  be passed to the autoload builtin; a typical use
              is +X to force the function to be loaded immediately.  Note that
              the -U and -z flags are always added implicitly.

       The  #  is part of the tag name and no white space is allowed after it.
       The #compdef tags use the compdef function described  below;  the  main
       difference is that the name of the function is supplied implicitly.

       The special contexts for which completion functions can be defined are:

       -array-value-
              The right hand side of an array-assignment (`name=(...)')

       -brace-parameter-
              The name of a parameter expansion within braces (`${...}')

       -assign-parameter-
              The  name of a parameter in an assignment, i.e. on the left hand
              side of an `='

       -command-
              A word in command position

       -condition-
              A word inside a condition (`[[...]]')

       -default-
              Any word for which no other completion is defined

       -equal-
              A word beginning with an equals sign

       -first-
              This is tried before any other completion function.   The  func-
              tion  called  may  set the _compskip parameter to one of various
              values: all: no further completion is attempted; a  string  con-
              taining  the substring patterns: no pattern completion functions
              will be called; a string containing default:  the  function  for
              the  `-default-'  context  will  not  be  called,  but functions
              defined for commands will be.

       -math- Inside mathematical contexts, such as `((...))'

       -parameter-
              The name of a parameter expansion (`$...')

       -redirect-
              The word after a redirection operator.

       -subscript-
              The contents of a parameter subscript.

       -tilde-
              After an initial tilde (`~'), but before the first slash in  the
              word.

       -value-
              On the right hand side of an assignment.

       Default  implementations  are  supplied for each of these contexts.  In
       most cases the context -context-  is  implemented  by  a  corresponding
       function  _context,  for example the context `-tilde-' and the function
       `_tilde').

       The contexts -redirect- and -value- allow extra context-specific infor-
       mation.  (Internally, this is handled by the functions for each context
       calling the function _dispatch.)  The extra information is added  sepa-
       rated by commas.

       For  the -redirect- context, the extra information is in the form `-re-
       direct-,op,command', where op is the redirection operator  and  command
       is  the name of the command on the line.  If there is no command on the
       line yet, the command field will be empty.

       For the -value- context, the form is `-value-,name,command', where name
       is  the  name of the parameter on the left hand side of the assignment.
       In  the  case  of  elements  of  an  associative  array,  for   example
       `assoc=(key <TAB>', name is expanded to `name-key'.  In certain special
       contexts, such as completing after `make  CFLAGS=',  the  command  part
       gives the name of the command, here make; otherwise it is empty.

       It  is  not necessary to define fully specific completions as the func-
       tions provided  will  try  to  generate  completions  by  progressively
       replacing  the elements with `-default-'.  For example, when completing
       after `foo=<TAB>', _value will try the names `-value-,foo,'  (note  the
       empty          command          part),          `-value-,foo,-default-'
       and`-value-,-default-,-default-', in that order, until it finds a func-
       tion to handle the context.

       As an example:

              compdef '_files -g "*.log"' '-redirect-,2>,-default-'

       completes  files matching `*.log' after `2> <TAB>' for any command with
       no more specific handler defined.

       Also:

              compdef _foo -value-,-default-,-default-

       specifies that _foo provides completions for the values  of  parameters
       for  which  no special function has been defined.  This is usually han-
       dled by the function _value itself.

       The same lookup rules are used when looking  up  styles  (as  described
       below); for example

              zstyle ':completion:*:*:-redirect-,2>,*:*' file-patterns '*.log'

       is  another  way  to  make  completion  after `2> <TAB>' complete files
       matching `*.log'.

   Functions
       The following function  is  defined  by  compinit  and  may  be  called
       directly.

       compdef [ -ane ] function name ... [ -{p|P} pattern ... [ -N name ...]]
       compdef -d name ...
       compdef -k [ -an ] function style key-sequence [ key-sequence ... ]
       compdef -K [ -an ] function name style key-seq [ name style seq ... ]
              The  first  form  defines the function to call for completion in
              the given contexts as described for the #compdef tag above.

              Alternatively, all the arguments may  have  the  form  `cmd=ser-
              vice'.   Here  service  should  already  have  been  defined  by
              `cmd1=service' lines in #compdef files, as described above.  The
              argument for cmd will be completed in the same way as service.

              The  function  argument may alternatively be a string containing
              almost any shell code.  If the string contains  an  equal  sign,
              the  above  will  take precedence.  The option -e may be used to
              specify the first argument is to be evaluated as shell code even
              if it contains an equal sign.  The string will be executed using
              the eval builtin command to generate completions.  This provides
              a  way  of  avoiding having to define a new completion function.
              For example, to complete files ending in `.h'  as  arguments  to
              the command foo:

                     compdef '_files -g "*.h"' foo

              The  option  -n prevents any completions already defined for the
              command or context from being overwritten.

              The option -d deletes any completion defined for the command  or
              contexts listed.

              The  names  may  also contain -p, -P and -N options as described
              for the #compdef tag.  The effect on the argument list is  iden-
              tical,  switching  between  definitions  of  patterns tried ini-
              tially, patterns tried finally, and  normal  commands  and  con-
              texts.

              The  parameter $_compskip may be set by any function defined for
              a pattern context.  If it is set to a value containing the  sub-
              string  `patterns' none of the pattern-functions will be called;
              if it is set to a value containing the substring `all', no other
              function will be called.

              The  form  with  -k  defines  a widget with the same name as the
              function that will be called for each of the key-sequences; this
              is  like  the #compdef -k tag.  The function should generate the
              completions needed and will otherwise behave  like  the  builtin
              widget  whose  name is given as the style argument.  The widgets
              usable  for  this   are:   complete-word,   delete-char-or-list,
              expand-or-complete,   expand-or-complete-prefix,   list-choices,
              menu-complete,  menu-expand-or-complete,  and  reverse-menu-com-
              plete,  as  well  as  menu-select  if the zsh/complist module is
              loaded.  The option -n prevents the key being  bound  if  it  is
              already to bound to something other than undefined-key.

              The  form  with -K is similar and defines multiple widgets based
              on the same function, each of which requires the  set  of  three
              arguments name, style and key-sequence, where the latter two are
              as for -k and the first must be a unique widget  name  beginning
              with an underscore.

              Wherever  applicable, the -a option makes the function autoload-
              able, equivalent to autoload -U function.

       The function compdef can be used to associate existing completion func-
       tions with new commands.  For example,

              compdef _pids foo

       uses the function _pids to complete process IDs for the command foo.

       Note  also the _gnu_generic function described below, which can be used
       to complete options for commands that understand the `--help' option.

COMPLETION SYSTEM CONFIGURATION
       This section gives a short overview of how the completion system works,
       and  then  more  detail on how users can configure how and when matches
       are generated.

   Overview
       When completion is attempted somewhere on the command line the  comple-
       tion system begins building the context.  The context represents every-
       thing that the shell knows about the meaning of the  command  line  and
       the  significance of the cursor position.  This takes account of a num-
       ber of things including the command word (such as `grep' or `zsh')  and
       options  to which the current word may be an argument (such as the `-o'
       option to zsh which takes a shell option as an argument).

       The context starts out very generic ("we are beginning  a  completion")
       and becomes more specific as more is learned ("the current word is in a
       position that is usually a command name" or "the current word might  be
       a  variable  name"  and so on).  Therefore the context will vary during
       the same call to the completion system.

       This context information is condensed into a string consisting of  mul-
       tiple  fields  separated by colons, referred to simply as `the context'
       in the remainder of the documentation.  Note that a user of the comple-
       tion  system rarely needs to compose a context string, unless for exam-
       ple a new function is being written to perform  completion  for  a  new
       command.   What a user may need to do is compose a style pattern, which
       is matched against a context when needed to look  up  context-sensitive
       options that configure the completion system.

       The  next  few  paragraphs explain how a context is composed within the
       completion function suite.  Following that is discussion of how  styles
       are  defined.  Styles determine such things as how the matches are gen-
       erated, similarly to shell options but with much  more  control.   They
       are defined with the zstyle builtin command (see zshmodules(1)).

       The  context string always consists of a fixed set of fields, separated
       by colons and with a leading colon before the first.  Fields which  are
       not yet known are left empty, but the surrounding colons appear anyway.
       The fields are always in the order  :completion:function:completer:com-
       mand:argument:tag.  These have the following meaning:

       o      The literal string completion, saying that this style is used by
              the completion system.   This  distinguishes  the  context  from
              those used by, for example, zle widgets and ZFTP functions.


       o      The function, if completion is called from a named widget rather
              than through the normal completion system.   Typically  this  is
              blank,  but  it is set by special widgets such as predict-on and
              the various functions in the Widget directory of  the  distribu-
              tion to the name of that function, often in an abbreviated form.


       o      The completer currently active, the name of the function without
              the leading underscore and with other underscores  converted  to
              hyphens.   A `completer' is in overall control of how completion
              is to be performed; `complete' is the simplest, but  other  com-
              pleters exist to perform related tasks such as correction, or to
              modify the behaviour of a  later  completer.   See  the  section
              `Control Functions' below for more information.


       o      The command or a special -context-, just at it appears following
              the #compdef tag or the compdef function.  Completion  functions
              for commands that have sub-commands usually modify this field to
              contain the name of the command followed by a minus sign and the
              sub-command.   For  example, the completion function for the cvs
              command sets this field to cvs-add when completing arguments  to
              the add subcommand.


       o      The  argument; this indicates which command line or option argu-
              ment we are completing.  For command  arguments  this  generally
              takes  the  form  argument-n, where n is the number of the argu-
              ment, and for arguments to options the form option-opt-n where n
              is  the  number of the argument to option opt.  However, this is
              only the case if  the  command  line  is  parsed  with  standard
              UNIX-style options and arguments, so many completions do not set
              this.


       o      The tag.  As described previously, tags are used to discriminate
              between  the types of matches a completion function can generate
              in a certain context.  Any completion function may use  any  tag
              name  it  likes,  but  a  list  of the more common ones is given
              below.


       The context is gradually put together as the  functions  are  executed,
       starting  with  the  main  entry point, which adds :completion: and the
       function element if necessary.  The completer then adds  the  completer
       element.   The  contextual  completion  adds  the  command and argument
       options.  Finally, the tag is added when the types  of  completion  are
       known.  For example, the context name

              :completion::complete:dvips:option-o-1:files

       says  that normal completion was attempted as the first argument to the
       option -o of the command dvips:

              dvips -o ...

       and the completion function will generate filenames.

       Usually completion will be tried for all  possible  tags  in  an  order
       given  by  the  completion  function.   However, this can be altered by
       using the tag-order style.  Completion is then restricted to  the  list
       of given tags in the given order.

       The  _complete_help  bindable  command  shows all the contexts and tags
       available for completion at a particular point.  This provides an  easy
       way  of  finding  information  for  tag-order  and other styles.  It is
       described in the section `Bindable Commands' below.

       When looking up styles the completion system uses full  context  names,
       including  the tag.  Looking up the value of a style therefore consists
       of two things: the context, which is matched to the most specific (best
       fitting) style pattern, and the name of the style itself, which must be
       matched exactly.  The following examples demonstrate  that  style  pat-
       terns  may  be  loosely  defined  for  styles that apply broadly, or as
       tightly defined as desired for styles that apply  in  narrower  circum-
       stances.

       For example, many completion functions can generate matches in a simple
       and a verbose form and use the  verbose  style  to  decide  which  form
       should be used.  To make all such functions use the verbose form, put

              zstyle ':completion:*' verbose yes

       in  a startup file (probably .zshrc).  This gives the verbose style the
       value yes in every context inside the completion  system,  unless  that
       context has a more specific definition.  It is best to avoid giving the
       context as `*' in case the style has some meaning outside  the  comple-
       tion system.

       Many  such general purpose styles can be configured simply by using the
       compinstall function.

       A more specific example of the use of the verbose style is by the  com-
       pletion  for  the kill builtin.  If the style is set, the builtin lists
       full job texts and process command lines; otherwise it shows  the  bare
       job numbers and PIDs.  To turn the style off for this use only:

              zstyle ':completion:*:*:kill:*:*' verbose no

       For  even  more  control,  the  style can use one of the tags `jobs' or
       `processes'.  To turn off verbose display only for jobs:

              zstyle ':completion:*:*:kill:*:jobs' verbose no

       The -e option to zstyle even allows completion function code to  appear
       as  the  argument  to  a style; this requires some understanding of the
       internals of completion functions (see see zshcompwid(1))).  For  exam-
       ple,

              zstyle -e ':completion:*' hosts 'reply=($myhosts)'

       This  forces  the value of the hosts style to be read from the variable
       myhosts each time a host name is needed; this is useful if the value of
       myhosts  can  change  dynamically.  For another useful example, see the
       example in the description of the file-list style below.  This form can
       be slow and should be avoided for commonly examined styles such as menu
       and list-rows-first.

       Note that the order in which styles are defined does  not  matter;  the
       style  mechanism uses the most specific possible match for a particular
       style to determine the set of values.  More precisely, strings are pre-
       ferred  over  patterns  (for  example, `:completion::complete:::foo' is
       more specific than `:completion::complete:::*'),  and  longer  patterns
       are preferred over shorter patterns.

       A good rule of thumb is that any completion style pattern that needs to
       include more than one wildcard (*) and that does not end in a tag name,
       should  include  all  six  colons  (:), possibly surrounding additional
       wildcards.

       Style names like those of tags are arbitrary and depend on the  comple-
       tion  function.   However,  the following two sections list some of the
       most common tags and styles.

   Standard Tags
       Some of the following are only used when looking up  particular  styles
       and do not refer to a type of match.

       accounts
              used to look up the users-hosts style

       all-expansions
              used by the _expand completer when adding the single string con-
              taining all possible expansions

       all-files
              for the names of all files (as distinct from a  particular  sub-
              set, see the globbed-files tag).

       arguments
              for arguments to a command

       arrays for names of array parameters

       association-keys
              for  keys  of  associative arrays; used when completing inside a
              subscript to a parameter of this type

       bookmarks
              when completing bookmarks (e.g. for URLs and the  zftp  function
              suite)

       builtins
              for names of builtin commands

       characters
              for  single  characters  in  arguments of commands such as stty.
              Also used when completing character  classes  after  an  opening
              bracket

       colormapids
              for X colormap ids

       colors for color names

       commands
              for  names  of external commands.  Also used by complex commands
              such as cvs when completing names subcommands.

       contexts
              for contexts in arguments to the zstyle builtin command

       corrections
              used by the _approximate and _correct  completers  for  possible
              corrections

       cursors
              for cursor names used by X programs

       default
              used  in  some  contexts to provide a way of supplying a default
              when more specific tags are also valid.  Note that this  tag  is
              used when only the function field of the context name is set

       descriptions
              used  when  looking up the value of the format style to generate
              descriptions for types of matches

       devices
              for names of device special files

       directories
              for names of directories -- local-directories  is  used  instead
              when  completing  arguments  of  cd and related builtin commands
              when the cdpath array is set

       directory-stack
              for entries in the directory stack

       displays
              for X display names

       domains
              for network domains

       email-plugin
              for  email  addresses  from  the  `_email-plugin'   backend   of
              _email_addresses

       expansions
              used  by  the _expand completer for individual words (as opposed
              to the complete set of expansions) resulting from the  expansion
              of a word on the command line

       extensions
              for X server extensions

       file-descriptors
              for numbers of open file descriptors

       files  the generic file-matching tag used by functions completing file-
              names

       fonts  for X font names

       fstypes
              for file system types (e.g. for the mount command)

       functions
              names of functions -- normally shell functions, although certain
              commands may understand other kinds of function

       globbed-files
              for filenames when the name has been generated by pattern match-
              ing

       groups for names of user groups

       history-words
              for words from the history

       hosts  for hostnames

       indexes
              for array indexes

       jobs   for jobs (as listed by the `jobs' builtin)

       interfaces
              for network interfaces

       keymaps
              for names of zsh keymaps

       keysyms
              for names of X keysyms

       libraries
              for names of system libraries

       limits for system limits

       local-directories
              for names of directories that are subdirectories of the  current
              working  directory  when  completing arguments of cd and related
              builtin commands (compare path-directories) -- when  the  cdpath
              array is unset, directories is used instead

       manuals
              for names of manual pages

       mailboxes
              for e-mail folders

       maps   for map names (e.g. NIS maps)

       messages
              used to look up the format style for messages

       modifiers
              for names of X modifiers

       modules
              for modules (e.g. zsh modules)

       my-accounts
              used to look up the users-hosts style

       named-directories
              for  named  directories  (you  wouldn't have guessed that, would
              you?)

       names  for all kinds of names

       newsgroups
              for USENET groups

       nicknames
              for nicknames of NIS maps

       options
              for command options

       original
              used by the _approximate, _correct and _expand  completers  when
              offering the original string as a match

       other-accounts
              used to look up the users-hosts style

       other-files
              for  the names of any non-directory files.  This is used instead
              of all-files when the list-dirs-first style is in effect.

       packages
              for packages (e.g. rpm or installed Debian packages)

       parameters
              for names of parameters

       path-directories
              for names of directories found by  searching  the  cdpath  array
              when  completing  arguments  of  cd and related builtin commands
              (compare local-directories)

       paths  used to look up the values of the  expand,  ambiguous  and  spe-
              cial-dirs styles

       pods   for perl pods (documentation files)

       ports  for communication ports

       prefixes
              for prefixes (like those of a URL)

       printers
              for print queue names

       processes
              for process identifiers

       processes-names
              used  to  look up the command style when generating the names of
              processes for killall

       sequences
              for sequences (e.g. mh sequences)

       sessions
              for sessions in the zftp function suite

       signals
              for signal names

       strings
              for strings (e.g. the replacement strings  for  the  cd  builtin
              command)

       styles for styles used by the zstyle builtin command

       suffixes
              for filename extensions

       tags   for tags (e.g. rpm tags)

       targets
              for makefile targets

       time-zones
              for time zones (e.g. when setting the TZ parameter)

       types  for types of whatever (e.g. address types for the xhost command)

       urls   used to look up the urls and local styles when completing URLs

       users  for usernames

       values for one of a set of values in certain lists

       variant
              used  by _pick_variant to look up the command to run when deter-
              mining what program is installed for a particular command name.

       visuals
              for X visuals

       warnings
              used to look up the format style for warnings

       widgets
              for zsh widget names

       windows
              for IDs of X windows

       zsh-options
              for shell options

   Standard Styles
       Note that the values of several of these styles represent boolean  val-
       ues.   Any  of the strings `true', `on', `yes', and `1' can be used for
       the value `true' and any of the strings `false', `off', `no',  and  `0'
       for  the  value `false'.  The behavior for any other value is undefined
       except where explicitly mentioned.  The default  value  may  be  either
       `true' or `false' if the style is not set.

       Some  of  these  styles  are tested first for every possible tag corre-
       sponding to a type of match, and if no style was found, for the default
       tag.   The  most  notable styles of this type are menu, list-colors and
       styles  controlling  completion  listing  such   as   list-packed   and
       last-prompt.   When tested for the default tag, only the function field
       of the context will be set so that a style using the default  tag  will
       normally be defined along the lines of:

              zstyle ':completion:*:default' menu ...

       accept-exact
              This is tested for the default tag in addition to the tags valid
              for the current context.  If it is set to `true' and any of  the
              trial  matches  is  the  same as the string on the command line,
              this match will immediately be accepted (even if it would other-
              wise be considered ambiguous).

              When  completing  pathnames (where the tag used is `paths') this
              style accepts any number of patterns as the value in addition to
              the  boolean  values.   Pathnames matching one of these patterns
              will be accepted immediately even if the command  line  contains
              some more partially typed pathname components and these match no
              file under the directory accepted.

              This style is also used by the _expand completer  to  decide  if
              words  beginning  with  a tilde or parameter expansion should be
              expanded.  For example, if there are parameters foo and  foobar,
              the  string  `$foo' will only be expanded if accept-exact is set
              to `true'; otherwise the completion system will  be  allowed  to
              complete  $foo  to  $foobar.  If the style is set to `continue',
              _expand will add the expansion as a  match  and  the  completion
              system will also be allowed to continue.

       accept-exact-dirs
              This  is used by filename completion.  Unlike accept-exact it is
              a boolean.  By default, filename completion examines all  compo-
              nents  of  a path to see if there are completions of that compo-
              nent, even if the component matches an existing directory.   For
              example,  when completion after /usr/bin/, the function examines
              possible completions to /usr.

              When this style is `true', any prefix of a path that matches  an
              existing  directory  is accepted without any attempt to complete
              it further.  Hence, in the given example, the path /usr/bin/  is
              accepted immediately and completion tried in that directory.

              This style is also useful when completing after directories that
              magically appear when referenced, such as ZFS  .zfs  directories
              or  NetApp  .snapshot  directories.   When  the style is set the
              shell does not check for the existence of the  directory  within
              the parent directory.

              If  you  wish  to  inhibit  this  behaviour  entirely,  set  the
              path-completion style (see below) to `false'.

       add-space
              This style is used by the _expand completer.  If  it  is  `true'
              (the  default), a space will be inserted after all words result-
              ing from the expansion, or a slash  in  the  case  of  directory
              names.   If  the  value is `file', the completer will only add a
              space to names of existing files.  Either a  boolean  `true'  or
              the value `file' may be combined with `subst', in which case the
              completer will not add a  space  to  words  generated  from  the
              expansion of a substitution of the form `$(...)' or `${...}'.

              The  _prefix completer uses this style as a simple boolean value
              to decide if a space should be inserted before the suffix.

       ambiguous
              This applies when completing non-final  components  of  filename
              paths,  in  other  words  those with a trailing slash.  If it is
              set, the cursor is left after  the  first  ambiguous  component,
              even  if  menu completion is in use.  The style is always tested
              with the paths tag.

       assign-list
              When completing after an equals sign that is being treated as an
              assignment,  the  completion  system normally completes only one
              filename.  In some cases the value  may be a list  of  filenames
              separated  by colons, as with PATH and similar parameters.  This
              style can be set to a list of patterns  matching  the  names  of
              such parameters.

              The  default  is  to  complete  lists  when the word on the line
              already contains a colon.

       auto-description
              If set, this style's value will be used as the  description  for
              options  that are not described by the completion functions, but
              that have exactly one argument.  The sequence `%d' in the  value
              will  be replaced by the description for this argument.  Depend-
              ing on personal preferences, it may be useful to set this  style
              to  something  like  `specify: %d'.  Note that this may not work
              for some commands.

       avoid-completer
              This is used by the _all_matches  completer  to  decide  if  the
              string  consisting  of  all  matches should be added to the list
              currently being generated.  Its value is a list of names of com-
              pleters.  If any of these is the name of the completer that gen-
              erated the matches in this completion, the string  will  not  be
              added.

              The  default value for this style is `_expand _old_list _correct
              _approximate', i.e. it  contains  the  completers  for  which  a
              string with all matches will almost never be wanted.

       cache-path
              This  style  defines  the  path where any cache files containing
              dumped completion data  are  stored.   It  defaults  to  `$ZDOT-
              DIR/.zcompcache',  or  `$HOME/.zcompcache'  if  $ZDOTDIR  is not
              defined.  The completion cache  will  not  be  used  unless  the
              use-cache style is set.

       cache-policy
              This  style  defines the function that will be used to determine
              whether a cache  needs  rebuilding.   See  the  section  on  the
              _cache_invalid function below.

       call-command
              This style is used in the function for commands such as make and
              ant where calling the command directly to generate matches  suf-
              fers  problems such as being slow or, as in the case of make can
              potentially cause actions in the makefile to be executed. If  it
              is  set to `true' the command is called to generate matches. The
              default value of this style is `false'.

       command
              In many places, completion functions need to call external  com-
              mands  to  generate  the list of completions.  This style can be
              used to override the command that is called in some such  cases.
              The  elements of the value are joined with spaces to form a com-
              mand line to execute.  The value can also start with  a  hyphen,
              in  which  case the usual command will be added to the end; this
              is most useful for putting `builtin' or `command'  in  front  to
              make  sure  the  appropriate version of a command is called, for
              example to avoid calling a shell function with the same name  as
              an external command.

              As an example, the completion function for process IDs uses this
              style with the processes tag to generate the IDs to complete and
              the  list  of  processes  to  display  (if  the verbose style is
              `true').  The list produced by the command should look like  the
              output  of the ps command.  The first line is not displayed, but
              is searched for the string `PID' (or `pid') to find the position
              of the process IDs in the following lines.  If the line does not
              contain `PID', the first numbers in each of the other lines  are
              taken as the process IDs to complete.

              Note  that  the  completion  function  generally has to call the
              specified command for each attempt to  generate  the  completion
              list.   Hence care should be taken to specify only commands that
              take a short time to run, and in particular to  avoid  any  that
              may never terminate.

       command-path
              This  is  a  list  of directories to search for commands to com-
              plete.  The default for this style is the value of  the  special
              parameter path.

       commands
              This  is  used  by  the function completing sub-commands for the
              system initialisation scripts (residing in /etc/init.d or  some-
              where  not too far away from that).  Its values give the default
              commands to complete for those commands for which the completion
              function isn't able to find them out automatically.  The default
              for this style are the two strings `start' and `stop'.

       complete
              This is used by the _expand_alias function  when  invoked  as  a
              bindable  command.  If set to `true' and the word on the command
              line is not the name of an alias, matching alias names  will  be
              completed.

       complete-options
              This  is  used  by  the  completer for cd, chdir and pushd.  For
              these commands a - is used to introduce a directory stack  entry
              and  completion  of  these  is  far  more common than completing
              options.  Hence unless the value of this style is `true' options
              will  not  be  completed,  even  after  an  initial -.  If it is
              `true', options will be completed  after  an  initial  -  unless
              there is a preceding -- on the command line.

       completer
              The  strings  given as the value of this style provide the names
              of the completer functions to use. The available completer func-
              tions are described in the section `Control Functions' below.

              Each  string may be either the name of a completer function or a
              string of the form `function:name'.  In the first case the  com-
              pleter  field  of  the context will contain the name of the com-
              pleter without the leading underscore and with all other  under-
              scores  replaced by hyphens.  In the second case the function is
              the name of the completer to call, but the context will  contain
              the user-defined name in the completer field of the context.  If
              the name starts with a hyphen, the string for the  context  will
              be build from the name of the completer function as in the first
              case with the name appended to it.  For example:

                     zstyle ':completion:*' completer _complete _complete:-foo

              Here, completion will call the _complete completer  twice,  once
              using  `complete' and once using `complete-foo' in the completer
              field of the context.  Normally, using the same  completer  more
              than  once  only makes sense when used with the `functions:name'
              form, because otherwise the context name will be the same in all
              calls to the completer; possible exceptions to this rule are the
              _ignored and _prefix completers.

              The default value for this style is `_complete  _ignored':  only
              completion  will be done, first using the ignored-patterns style
              and the $fignore array and then without ignoring matches.

       condition
              This style is used by the _list completer function to decide  if
              insertion  of  matches  should  be  delayed unconditionally. The
              default is `true'.

       delimiters
              This style is used when adding a delimiter for use with  history
              modifiers  or glob qualifiers that have delimited arguments.  It
              is an array of preferred delimiters to add.  Non-special charac-
              ters are preferred as the completion system may otherwise become
              confused.  The default list is :, +, /, -, %.  The list  may  be
              empty to force a delimiter to be typed.

       disabled
              If  this is set to `true', the _expand_alias completer and bind-
              able command will try to  expand  disabled  aliases,  too.   The
              default is `false'.

       domains
              A  list  of names of network domains for completion.  If this is
              not  set,  domain  names   will   be   taken   from   the   file
              /etc/resolv.conf.

       environ
              The environ style is used when completing for `sudo'.  It is set
              to an array of `VAR=value' assignments to be exported  into  the
              local  environment  before the completion for the target command
              is invoked.
              zstyle ':completion:*:sudo::' environ \
                PATH="/sbin:/usr/sbin:$PATH" HOME="/root"

       expand This style is used when completing strings consisting of  multi-
              ple parts, such as path names.

              If one of its values is the string `prefix', the partially typed
              word from the line will be expanded as far as possible  even  if
              trailing parts cannot be completed.

              If  one of its values is the string `suffix', matching names for
              components after the first ambiguous one  will  also  be  added.
              This  means that the resulting string is the longest unambiguous
              string possible.  However, menu completion can be used to  cycle
              through all matches.

       fake   This  style may be set for any completion context.  It specifies
              additional strings that will always be completed  in  that  con-
              text.  The form of each string is `value:description'; the colon
              and description may be omitted, but any literal colons in  value
              must  be  quoted  with a backslash.  Any description provided is
              shown alongside the value in completion listings.

              It is important to use a sufficiently restrictive  context  when
              specifying  fake  strings.   Note that the styles fake-files and
              fake-parameters  provide  additional  features  when  completing
              files or parameters.

       fake-always
              This  works  identically  to  the  fake  style  except  that the
              ignored-patterns style is not applied to it.  This makes it pos-
              sible  to  override  a  set of matches completely by setting the
              ignored patterns to `*'.

              The following shows a way of supplementing any  tag  with  arbi-
              trary  data,  but  having  it behave for display purposes like a
              separate tag.  In this  example  we  use  the  features  of  the
              tag-order  style  to  divide  the named-directories tag into two
              when performing completion with the standard completer  complete
              for  arguments  of cd.  The tag named-directories-normal behaves
              as normal, but the tag named-directories-mine contains  a  fixed
              set  of  directories.   This  has the effect of adding the match
              group `extra directories' with the given completions.

                     zstyle ':completion::complete:cd:*' tag-order \
                       'named-directories:-mine:extra\ directories
                       named-directories:-normal:named\ directories *'
                     zstyle ':completion::complete:cd:*:named-directories-mine' \
                       fake-always mydir1 mydir2
                     zstyle ':completion::complete:cd:*:named-directories-mine' \
                       ignored-patterns '*'

       fake-files
              This style is used when completing files and looked up without a
              tag.   Its values are of the form `dir:names...'.  This will add
              the names (strings separated by spaces) as possible matches when
              completing  in  the  directory dir, even if no such files really
              exist.  The dir may be a pattern; pattern characters  or  colons
              in  dir  should  be quoted with a backslash to be treated liter-
              ally.

              This can be useful on systems that support special file  systems
              whose  top-level  pathnames  can not be listed or generated with
              glob patterns (but see accept-exact-dirs for a more general  way
              of dealing with this problem).  It can also be used for directo-
              ries for which one does not have read permission.

              The pattern form can be used to add a certain `magic'  entry  to
              all directories on a particular file system.

       fake-parameters
              This  is  used  by  the completion function for parameter names.
              Its values are names of parameters that might not yet be set but
              should be completed nonetheless.  Each name may also be followed
              by a colon and a string specifying the  type  of  the  parameter
              (like  `scalar',  `array'  or `integer').  If the type is given,
              the name will only be completed if parameters of that  type  are
              required  in the particular context.  Names for which no type is
              specified will always be completed.

       file-list
              This style controls whether files completed using  the  standard
              builtin  mechanism  are to be listed with a long list similar to
              ls -l.  Note that this feature uses the  shell  module  zsh/stat
              for  file  information;  this  loads the builtin stat which will
              replace any external stat executable.  To avoid this the follow-
              ing code can be included in an initialization file:

                     zmodload -i zsh/stat
                     disable stat

              The style may either be set to a `true' value (or `all'), or one
              of the values `insert' or `list', indicating that files  are  to
              be  listed in long format in all circumstances, or when attempt-
              ing to insert a file name, or when listing  file  names  without
              attempting to insert one.

              More  generally,  the  value may be an array of any of the above
              values, optionally followed by =num.  If num is present it gives
              the  maximum number of matches for which long listing style will
              be used.  For example,

                     zstyle ':completion:*' file-list list=20 insert=10

              specifies that long format will be used when listing  up  to  20
              files  or  inserting  a  file  with up to 10 matches (assuming a
              listing is to be shown at all, for example on an ambiguous  com-
              pletion), else short format will be used.

                     zstyle -e ':completion:*' file-list \
                            '(( ${+NUMERIC} )) && reply=(true)'

              specifies that long format will be used any time a numeric argu-
              ment is supplied, else short format.

       file-patterns
              This is used by the standard function for completing  filenames,
              _files.   If  the  style  is unset up to three tags are offered,
              `globbed-files',`directories' and `all-files', depending on  the
              types of files  expected by the caller of _files.  The first two
              (`globbed-files'  and  `directories')   are   normally   offered
              together to make it easier to complete files in sub-directories.

              The  file-patterns  style  provides  alternatives to the default
              tags, which are not used.  Its value consists of elements of the
              form  `pattern:tag';  each string may contain any number of such
              specifications separated by spaces.

              The pattern is a pattern that is to be used  to  generate  file-
              names.   Any  occurrence of the sequence `%p' is replaced by any
              pattern(s) passed by the function calling _files.  Colons in the
              pattern  must  be  preceded  by a backslash to make them distin-
              guishable from the colon before the tag.  If more than one  pat-
              tern  is  needed, the patterns can be given inside braces, sepa-
              rated by commas.

              The tags of all strings in the value will be offered  by  _files
              and  used  when  looking  up other styles.  Any tags in the same
              word will be offered at the same time and  before  later  words.
              If no `:tag' is given the `files' tag will be used.

              The  tag  may also be followed by an optional second colon and a
              description, which will be used for the `%d' in the value of the
              format style (if that is set) instead of the default description
              supplied by the completion function.  If the  description  given
              here  contains itself a `%d', that is replaced with the descrip-
              tion supplied by the completion function.

              For example, to make the rm command first complete only names of
              object  files  and  then  the  names of all files if there is no
              matching object file:

                     zstyle ':completion:*:*:rm:*:*' file-patterns \
                         '*.o:object-files' '%p:all-files'

              To alter the default behaviour of file completion -- offer files
              matching  a  pattern  and directories on the first attempt, then
              all files -- to offer only matching files on the first  attempt,
              then directories, and finally all files:

                     zstyle ':completion:*' file-patterns \
                         '%p:globbed-files' '*(-/):directories' '*:all-files'

              This  works  even  where  there  is  no  special pattern: _files
              matches all files using the pattern `*' at the  first  step  and
              stops  when it sees this pattern.  Note also it will never try a
              pattern more than once for a single completion attempt.

              During the execution of completion functions, the  EXTENDED_GLOB
              option  is  in  effect,  so the characters `#', `~' and `^' have
              special meanings in the patterns.

       file-sort
              The standard filename completion function uses this style  with-
              out  a  tag  to  determine  in  which  order the names should be
              listed; menu completion will cycle  through  them  in  the  same
              order.   The  possible values are: `size' to sort by the size of
              the file; `links' to sort by the number of links  to  the  file;
              `modification' (or `time' or `date') to sort by the last modifi-
              cation time; `access' to sort  by  the  last  access  time;  and
              `inode' (or `change') to sort by the last inode change time.  If
              the style is set to any other value, or is unset, files will  be
              sorted alphabetically by name.  If the value contains the string
              `reverse', sorting is done in the opposite order.  If the  value
              contains the string `follow', timestamps are associated with the
              targets of symbolic links; the default is to use the  timestamps
              of the links themselves.

       filter The    ldap    plugin   of   email   address   completion   (see
              _email_addresses) uses this style to specify the  attributes  to
              match  against  when  filtering entries.  So for example, if the
              style is set to `sn', matching is done against surnames.   Stan-
              dard  LDAP  filtering  is  used so normal completion matching is
              bypassed.  If this style is not set, the LDAP plugin is skipped.
              You  may  also  need  to set the command style to specify how to
              connect to your LDAP server.

       force-list
              This forces a list of completions to be shown at any point where
              listing  is  done, even in cases where the list would usually be
              suppressed.  For example, normally the list  is  only  shown  if
              there are at least two different matches.  By setting this style
              to `always', the list will always be shown,  even  if  there  is
              only  a  single  match  that  will immediately be accepted.  The
              style may also be set to a number.  In this case the  list  will
              be  shown  if there are at least that many matches, even if they
              would all insert the same string.

              This style is tested for the default tag as well as for each tag
              valid  for  the  current  completion.   Hence the listing can be
              forced only for certain types of match.

       format If this is set for the descriptions tag, its value is used as  a
              string  to  display  above  matches  in  completion  lists.  The
              sequence `%d' in this string  will  be  replaced  with  a  short
              description  of  what  these  matches are.  This string may also
              contain the following sequences to specify output attributes  as
              described  in  the section EXPANSION OF PROMPT SEQUENCES in zsh-
              misc(1): `%B', `%S', `%U', `%F', `%K' and their lower case coun-
              terparts,  as  well as `%{...%}'.  `%F', `%K' and `%{...%}' take
              arguments in the same form as prompt expansion.  Note  that  the
              sequence  `%G'  is  not available; an argument to `%{' should be
              used instead.

              The style is tested with each tag valid for the current  comple-
              tion  before  it is tested for the descriptions tag.  Hence dif-
              ferent format strings can be  defined  for  different  types  of
              match.

              Note  also  that  some  completer  functions  define  additional
              `%'-sequences.  These are described for the completer  functions
              that make use of them.

              Some  completion  functions  display  messages  that may be cus-
              tomised by setting this style for the messages tag.   Here,  the
              `%d'  is  replaced  with a message given by the completion func-
              tion.

              Finally, the format string is looked up with the  warnings  tag,
              for use when no matches could be generated at all.  In this case
              the `%d' is replaced with the descriptions for the matches  that
              were  expected  separated  by  spaces.   The  sequence  `%D'  is
              replaced with the same descriptions separated by newlines.

              It is possible to use printf-style field width  specifiers  with
              `%d' and similar escape sequences.  This is handled by the zfor-
              mat builtin command  from  the  zsh/zutil  module,  see  zshmod-
              ules(1).

       glob   This  is  used by the _expand completer.  If it is set to `true'
              (the default), globbing will be attempted on the words resulting
              from  a previous substitution (see the substitute style) or else
              the original string from the line.

       global If this is set to `true' (the default), the  _expand_alias  com-
              pleter and bindable command will try to expand global aliases.

       group-name
              The  completion  system  can  group  different types of matches,
              which appear in separate lists.  This style can be used to  give
              the  names  of groups for particular tags.  For example, in com-
              mand position the completion system generates names  of  builtin
              and  external  commands,  names  of aliases, shell functions and
              parameters and reserved words as possible completions.  To  have
              the external commands and shell functions listed separately:

                     zstyle ':completion:*:*:-command-:*:commands' \
                            group-name commands
                     zstyle ':completion:*:*:-command-:*:functions' \
                            group-name functions

              As  a consequence, any match with the same tag will be displayed
              in the same group.

              If the name given is the empty string the name of  the  tag  for
              the  matches will be used as the name of the group.  So, to have
              all different types of matches  displayed  separately,  one  can
              just set:

                     zstyle ':completion:*' group-name ''

              All  matches for which no group name is defined will be put in a
              group named -default-.

       group-order
              This style is additional to the group-name style to specify  the
              order  for  display of the groups defined by that style (compare
              tag-order, which determines which completions  appear  at  all).
              The  groups named are shown in the given order; any other groups
              are shown in the order defined by the completion function.

              For example, to have names of builtin commands, shell  functions
              and  external  commands  appear in that order when completing in
              command position:

                     zstyle ':completion:*:*:-command-:*:*' group-order \
                            builtins functions commands

       groups A list of names of UNIX groups.  If this is not set, group names
              are taken from the YP database or the file `/etc/group'.

       hidden If this is set to `true', matches for the given context will not
              be listed, although any description for the matches set with the
              format style will be shown.  If it is set to `all', not even the
              description will be displayed.

              Note that the matches will still be completed; they are just not
              shown in the list.  To avoid having matches considered as possi-
              ble completions at all, the tag-order style can be  modified  as
              described below.

       hosts  A  list  of names of hosts that should be completed.  If this is
              not set, hostnames are taken from the file `/etc/hosts'.

       hosts-ports
              This style is used by commands that need or accept hostnames and
              network  ports.   The strings in the value should be of the form
              `host:port'.  Valid ports are  determined  by  the  presence  of
              hostnames; multiple ports for the same host may appear.

       ignore-line
              This  is  tested  for each tag valid for the current completion.
              If it is set to `true', none of the words that  are  already  on
              the  line  will be considered as possible completions.  If it is
              set to `current', the word the cursor is on will not be  consid-
              ered  as  a  possible  completion.  The value `current-shown' is
              similar but only applies if the list of completions is currently
              shown  on  the screen.  Finally, if the style is set to `other',
              all words on the  line  except  for  the  current  one  will  be
              excluded from the possible completions.

              The  values  `current'  and  `current-shown'  are a bit like the
              opposite of the accept-exact style:  only strings  with  missing
              characters will be completed.

              Note  that you almost certainly don't want to set this to `true'
              or `other' for a general context such as `:completion:*'.   This
              is because it would disallow completion of, for example, options
              multiple times even if  the  command  in  question  accepts  the
              option more than once.

       ignore-parents
              The  style  is  tested  without a tag by the function completing
              pathnames in order to determine whether to ignore the  names  of
              directories  already  mentioned in the current word, or the name
              of the current working directory.  The value must include one or
              both of the following strings:

              parent The name of any directory whose path is already contained
                     in the word on the line is ignored.   For  example,  when
                     completing  after  foo/../, the directory foo will not be
                     considered a valid completion.

              pwd    The name of the current working  directory  will  not  be
                     completed;  hence, for example, completion after ../ will
                     not use the name of the current directory.

              In addition, the value may include one or both of:

              ..     Ignore the specified directories only when  the  word  on
                     the line contains the substring `../'.

              directory
                     Ignore  the  specified  directories  only  when  names of
                     directories are completed, not when completing  names  of
                     files.

              Excluded  values  act  in  a  similar  fashion  to values of the
              ignored-patterns style, so they can be restored to consideration
              by the _ignored completer.

       extra-verbose
              If  set, the completion listing is more verbose at the cost of a
              probable decrease in completion speed.   Completion  performance
              will suffer if this style is set to `true'.

       ignored-patterns
              A  list  of  patterns;  any trial completion matching one of the
              patterns will be excluded from consideration.  The _ignored com-
              pleter  can  appear  in  the  list  of completers to restore the
              ignored matches.  This is a more  configurable  version  of  the
              shell parameter $fignore.

              Note  that  the EXTENDED_GLOB option is set during the execution
              of completion functions, so the characters `#', `~' and `^' have
              special meanings in the patterns.

       insert This  style  is  used  by  the  _all_matches completer to decide
              whether to  insert  the  list  of  all  matches  unconditionally
              instead of adding the list as another match.

       insert-ids
              When  completing  process  IDs,  for example as arguments to the
              kill and wait builtins the name of a command may be converted to
              the  appropriate  process ID.  A problem arises when the process
              name typed is not unique.  By default (or if this style  is  set
              explicitly  to `menu') the name will be converted immediately to
              a set of possible IDs, and menu completion will  be  started  to
              cycle through them.

              If the value of the style is `single', the shell will wait until
              the user has typed enough to make the command unique before con-
              verting the name to an ID; attempts at completion will be unsuc-
              cessful until that point.  If the value  is  any  other  string,
              menu  completion  will  be  started when the string typed by the
              user is longer than the common prefix to the corresponding IDs.

       insert-tab
              If this is set to `true', the completion system  will  insert  a
              TAB  character  (assuming  that  was  used  to start completion)
              instead of performing completion  when  there  is  no  non-blank
              character  to  the left of the cursor.  If it is set to `false',
              completion will be done even there.

              The value may also contain the substrings  `pending'  or  `pend-
              ing=val'.   In  this  case, the typed character will be inserted
              instead of starting completion when there is  unprocessed  input
              pending.   If  a  val  is  given, completion will not be done if
              there are at least that many characters  of  unprocessed  input.
              This  is  often  useful when pasting characters into a terminal.
              Note however, that it relies on the $PENDING  special  parameter
              from  the zsh/zle module being set properly which is not guaran-
              teed on all platforms.

              The default value of this style is `true' except for  completion
              within vared builtin command where it is `false'.

       insert-unambiguous
              This  is  used by the _match and _approximate completers.  These
              completers are often used with menu completion  since  the  word
              typed may bear little resemblance to the final completion.  How-
              ever, if this style is `true', the  completer  will  start  menu
              completion  only  if it could find no unambiguous initial string
              at least as long as the original string typed by the user.

              In the case of the _approximate completer, the  completer  field
              in  the context will already have been set to one of correct-num
              or approximate-num, where num is the number of errors that  were
              accepted.

              In  the  case of the _match completer, the style may also be set
              to the string `pattern'.  Then the pattern on the line  is  left
              unchanged if it does not match unambiguously.

       gain-privileges
              If set to true, this style enables the use of commands like sudo
              or doas to gain extra privileges when retrieving information for
              completion.  This  is  only  done  when  a  command such as sudo
              appears on the command-line. To force the use of, e.g.  sudo  or
              to  override  any  prefix that might be added due to gain-privi-
              leges, the command style can be used with a  value  that  begins
              with a hyphen.

       keep-prefix
              This  style  is used by the _expand completer.  If it is `true',
              the completer will try to keep a prefix containing  a  tilde  or
              parameter  expansion.   Hence,  for  example,  the string `~/f*'
              would be expanded to `~/foo' instead  of  `/home/user/foo'.   If
              the  style  is  set  to `changed' (the default), the prefix will
              only be left unchanged if there were other changes  between  the
              expanded words and the original word from the command line.  Any
              other value forces the prefix to be expanded unconditionally.

              The behaviour of _expand when this style is `true' is  to  cause
              _expand  to  give  up  when a single expansion with the restored
              prefix is the same as the original;  hence  any  remaining  com-
              pleters may be called.

       last-prompt
              This  is  a more flexible form of the ALWAYS_LAST_PROMPT option.
              If it is `true', the completion system will try  to  return  the
              cursor  to  the previous command line after displaying a comple-
              tion list.  It is tested for all tags valid for the current com-
              pletion, then the default tag.  The cursor will be moved back to
              the previous line if this style  is  `true'  for  all  types  of
              match.   Note  that unlike the ALWAYS_LAST_PROMPT option this is
              independent of the numeric argument.

       known-hosts-files
              This style should contain a list of files  to  search  for  host
              names  and (if the use-ip style is set) IP addresses in a format
              compatible with ssh known_hosts files.  If it is  not  set,  the
              files /etc/ssh/ssh_known_hosts and ~/.ssh/known_hosts are used.

       list   This  style  is used by the _history_complete_word bindable com-
              mand.  If it is set to `true' it has no effect.  If it is set to
              `false'  matches will not be listed.  This overrides the setting
              of the options  controlling  listing  behaviour,  in  particular
              AUTO_LIST.   The  context  always  starts with `:completion:his-
              tory-words'.

       list-colors
              If the zsh/complist module is loaded, this style can be used  to
              set  color  specifications.   This mechanism replaces the use of
              the ZLS_COLORS and ZLS_COLOURS parameters described in the  sec-
              tion  `The zsh/complist Module' in zshmodules(1), but the syntax
              is the same.

              If this style is set for the default tag,  the  strings  in  the
              value  are  taken  as  specifications that are to be used every-
              where.  If it is set for other tags, the specifications are used
              only  for matches of the type described by the tag.  For this to
              work best, the group-name style must be set to an empty string.

              In addition to setting styles for specific tags, it is also pos-
              sible  to use group names specified explicitly by the group-name
              tag together with the `(group)' syntax allowed by the ZLS_COLORS
              and ZLS_COLOURS parameters and simply using the default tag.

              It  is  possible  to use any color specifications already set up
              for the GNU version of the ls command:

                     zstyle ':completion:*:default' list-colors \
                            ${(s.:.)LS_COLORS}

              The default colors are the same as for the GNU  ls  command  and
              can  be  obtained  by setting the style to an empty string (i.e.
              '').

       list-dirs-first
              This is used by file completion.  If set, directories to be com-
              pleted  are  listed  separately  from  and before completion for
              other files, regardless of tag ordering.  In addition,  the  tag
              other-files  is  used  in  place  of all-files for the remaining
              files, to indicate that no directories are presented  with  that
              tag.

       list-grouped
              If  this  style  is  `true' (the default), the completion system
              will try to make certain completion  listings  more  compact  by
              grouping  matches.   For example, options for commands that have
              the same description (shown when the verbose  style  is  set  to
              `true')  will appear as a single entry.  However, menu selection
              can be used to cycle through all the matches.

       list-packed
              This is tested for each tag valid in the current context as well
              as  the  default tag.  If it is set to `true', the corresponding
              matches appear in listings as if  the  LIST_PACKED  option  were
              set.  If it is set to `false', they are listed normally.

       list-prompt
              If  this style is set for the default tag, completion lists that
              don't fit on the screen can be scrolled (see the description  of
              the  zsh/complist  module  in zshmodules(1)).  The value, if not
              the empty string, will be displayed after  every  screenful  and
              the  shell  will  prompt for a key press; if the style is set to
              the empty string, a default prompt will be used.

              The value may contain the escape sequences: `%l' or `%L',  which
              will  be  replaced  by the number of the last line displayed and
              the total number of lines; `%m' or `%M', the number of the  last
              match  shown and the total number of matches; and `%p' and `%P',
              `Top' when at the beginning of the list, `Bottom'  when  at  the
              end  and  the position shown as a percentage of the total length
              otherwise.  In each case the form with the uppercase letter will
              be  replaced  by  a  string of fixed width, padded to the  right
              with spaces, while the lowercase form  will  be  replaced  by  a
              variable  width  string.  As in other prompt strings, the escape
              sequences `%S', `%s', `%B', `%b', `%U', `%u'  for  entering  and
              leaving  the  display  modes  standout,  bold and underline, and
              `%F', `%f', `%K', `%k' for changing  the  foreground  background
              colour, are also available, as is the form `%{...%}' for enclos-
              ing escape sequences which display with zero (or, with a numeric
              argument, some other) width.

              After  deleting  this  prompt  the variable LISTPROMPT should be
              unset for the removal to take effect.

       list-rows-first
              This style is tested in the same way as  the  list-packed  style
              and  determines whether matches are to be listed in a rows-first
              fashion as if the LIST_ROWS_FIRST option were set.

       list-suffixes
              This style is used by the function that completes filenames.  If
              it is `true', and completion is attempted on a string containing
              multiple partially typed pathname components, all ambiguous com-
              ponents will be shown.  Otherwise, completion stops at the first
              ambiguous component.

       list-separator
              The value of this style is used in completion listing  to  sepa-
              rate  the  string  to  complete from a description when possible
              (e.g. when  completing  options).   It  defaults  to  `--'  (two
              hyphens).

       local  This  is for use with functions that complete URLs for which the
              corresponding files are available directly from the file system.
              Its  value should consist of three strings: a hostname, the path
              to the default web pages for the server, and the directory  name
              used by a user placing web pages within their home area.

              For example:

                     zstyle ':completion:*' local toast \
                         /var/http/public/toast public_html

              Completion  after  `http://toast/stuff/'  will look for files in
              the directory  /var/http/public/toast/stuff,   while  completion
              after  `http://toast/~yousir/' will look for files in the direc-
              tory ~yousir/public_html.

       mail-directory
              If set, zsh will assume that mailbox files can be found  in  the
              directory specified.  It defaults to `~/Mail'.

       match-original
              This  is  used  by  the _match completer.  If it is set to only,
              _match will try to generate matches without inserting a  `*'  at
              the  cursor  position.   If set to any other non-empty value, it
              will first try to generate matches without inserting the `*' and
              if  that  yields  no  matches,  it  will  try again with the `*'
              inserted.  If it is unset or set to the empty  string,  matching
              will only be performed with the `*' inserted.

       matcher
              This  style  is tested separately for each tag valid in the cur-
              rent context.  Its value is placed before any  match  specifica-
              tions  given  by the matcher-list style so can override them via
              the use of an x: specification.  The value should be in the form
              described  in  the section `Completion Matching Control' in zsh-
              compwid(1).  For examples of this, see the  description  of  the
              tag-order style.

       matcher-list
              This style can be set to a list of match specifications that are
              to be applied everywhere. Match specifications are described  in
              the section `Completion Matching Control' in zshcompwid(1).  The
              completion system will try them one after another for each  com-
              pleter  selected.   For  example, to try first simple completion
              and, if that generates no matches, case-insensitive completion:

                     zstyle ':completion:*' matcher-list '' 'm:{a-zA-Z}={A-Za-z}'

              By default each specification replaces the  previous  one;  how-
              ever,  if a specification is prefixed with +, it is added to the
              existing list.  Hence it is possible to create increasingly gen-
              eral specifications without repetition:

                     zstyle ':completion:*' matcher-list \
                            '' '+m:{a-z}={A-Z}' '+m:{A-Z}={a-z}'

              It is possible to create match specifications valid for particu-
              lar completers by using the third field of  the  context.   This
              applies   only   to   completers   that   override   the  global
              matcher-list, which as of this writing includes only _prefix and
              _ignored.   For  example,  to  use  the completers _complete and
              _prefix but allow case-insensitive completion  only  with  _com-
              plete:

                     zstyle ':completion:*' completer _complete _prefix
                     zstyle ':completion:*:complete:*:*:*' matcher-list \
                            '' 'm:{a-zA-Z}={A-Za-z}'

              User-defined  names,  as  explained for the completer style, are
              available.  This makes it possible to  try  the  same  completer
              more  than  once  with different match specifications each time.
              For example, to try normal completion without a match specifica-
              tion,  then  normal  completion  with case-insensitive matching,
              then correction, and finally partial-word completion:

                     zstyle ':completion:*' completer \
                         _complete _correct _complete:foo
                     zstyle ':completion:*:complete:*:*:*' matcher-list \
                         '' 'm:{a-zA-Z}={A-Za-z}'
                     zstyle ':completion:*:foo:*:*:*' matcher-list \
                         'm:{a-zA-Z}={A-Za-z} r:|[-_./]=* r:|=*'

              If the style is unset in any context no match  specification  is
              applied.   Note  also  that some completers such as _correct and
              _approximate do not use the match specifications at all,  though
              these  completers  will  only  ever  be  called once even if the
              matcher-list contains more than one element.

              Where multiple specifications are useful, note that  the  entire
              completion  is  done for each element of matcher-list, which can
              quickly reduce the shell's performance.   As  a  rough  rule  of
              thumb,  one  to  three strings will give acceptable performance.
              On the other hand, putting multiple space-separated values  into
              the  same  string does not have an appreciable impact on perfor-
              mance.

              If there is no current matcher or it is empty,  and  the  option
              NO_CASE_GLOB  is  in effect, the matching for files is performed
              case-insensitively in  any  case.   However,  any  matcher  must
              explicitly   specify   case-insensitive   matching  if  that  is
              required.

       max-errors
              This is used by the _approximate and  _correct  completer  func-
              tions  to  determine the maximum number of errors to allow.  The
              completer will try to generate completions by first allowing one
              error,  then  two  errors,  and  so  on, until either a match or
              matches were found or the maximum number of errors given by this
              style has been reached.

              If  the  value for this style contains the string `numeric', the
              completer function will take any numeric argument as the maximum
              number of errors allowed. For example, with

                     zstyle ':completion:*:approximate:::' max-errors 2 numeric

              two errors are allowed if no numeric argument is given, but with
              a numeric argument of six (as in `ESC-6 TAB'), up to six  errors
              are  accepted.  Hence with a value of `0 numeric', no correcting
              completion will be attempted unless a numeric argument is given.

              If the value contains the string  `not-numeric',  the  completer
              will  not  try  to  generate  corrected completions when given a
              numeric argument, so in this case the  number  given  should  be
              greater  than zero.  For example, `2 not-numeric' specifies that
              correcting completion with two errors will usually be performed,
              but  if  a numeric argument is given, correcting completion will
              not be performed.

              The default value for this style is `2 numeric'.

       max-matches-width
              This style is used to determine the trade off between the  width
              of  the  display  used  for matches and the width used for their
              descriptions when the verbose style is  in  effect.   The  value
              gives  the number of display columns to reserve for the matches.
              The default is half the width of the screen.

              This has the most impact when  several  matches  have  the  same
              description  and  so  will  be grouped together.  Increasing the
              style will allow more matches to be grouped together; decreasing
              it will allow more of the description to be visible.

       menu   If  this is `true' in the context of any of the tags defined for
              the current completion menu completion will be used.  The  value
              for  a  specific  tag  will  take  precedence  over that for the
              `default' tag.

              If none of the values found in this way is `true' but  at  least
              one  is  set  to  `auto',  the shell behaves as if the AUTO_MENU
              option is set.

              If one of the values is explicitly set to `false', menu  comple-
              tion will be explicitly turned off, overriding the MENU_COMPLETE
              option and other settings.

              In the form `yes=num', where `yes' may be any of the `true' val-
              ues  (`yes',  `true',  `on'  and  `1'),  menu completion will be
              turned on if there are  at  least  num  matches.   In  the  form
              `yes=long',  menu  completion will be turned on if the list does
              not fit on the screen.  This does not activate  menu  completion
              if  the widget normally only lists completions, but menu comple-
              tion  can  be  activated   in   that   case   with   the   value
              `yes=long-list'   (Typically,   the   value   `select=long-list'
              described later is more  useful  as  it  provides  control  over
              scrolling.)

              Similarly,  with any of the `false' values (as in `no=10'), menu
              completion will not be used if there are num or more matches.

              The value of this widget also controls menu selection, as imple-
              mented  by  the  zsh/complist  module.  The following values may
              appear either alongside or instead of the values above.

              If the value contains the string `select', menu  selection  will
              be started unconditionally.

              In the form `select=num', menu selection will only be started if
              there are at least num matches.  If the values for more than one
              tag provide a number, the smallest number is taken.

              Menu  selection can be turned off explicitly by defining a value
              containing the string`no-select'.

              It is also possible to start menu selection only if the list  of
              matches   does  not  fit  on  the  screen  by  using  the  value
              `select=long'.  To start menu selection even if the current wid-
              get only performs listing, use the value `select=long-list'.

              To  turn  on  menu completion or menu selection when there are a
              certain number of matches or the list of matches does not fit on
              the  screen,  both  of  `yes=' and `select=' may be given twice,
              once with a number and once with `long' or `long-list'.

              Finally, it is possible to activate two special  modes  of  menu
              selection.   The word `interactive' in the value causes interac-
              tive mode to be  entered  immediately  when  menu  selection  is
              started;  see the description of the zsh/complist module in zsh-
              modules(1) for a description of interactive mode.  Including the
              string  `search'  does the same for incremental search mode.  To
              select  backward  incremental   search,   include   the   string
              `search-backward'.

       muttrc If  set,  gives the location of the mutt configuration file.  It
              defaults to `~/.muttrc'.

       numbers
              This is used with the jobs tag.  If it is `true', the shell will
              complete  job numbers instead of the shortest unambiguous prefix
              of the job command text.  If the value is a number, job  numbers
              will  only  be used if that many words from the job descriptions
              are required to resolve ambiguities.  For example, if the  value
              is  `1',  strings  will  only  be used if all jobs differ in the
              first word on their command lines.

       old-list
              This is used by  the  _oldlist  completer.   If  it  is  set  to
              `always',  then  standard  widgets  which  perform  listing will
              retain the current list of matches, however they were generated;
              this can be turned off explicitly with the value `never', giving
              the behaviour without the _oldlist completer.  If the  style  is
              unset, or any other value, then the existing list of completions
              is displayed if it is not already; otherwise, the standard  com-
              pletion  list  is  generated;  this  is the default behaviour of
              _oldlist.  However, if there is an old list and this style  con-
              tains  the  name  of  the  completer function that generated the
              list, then the old list will be used even if it was generated by
              a widget which does not do listing.

              For  example, suppose you type ^Xc to use the _correct_word wid-
              get, which generates a list of corrections for  the  word  under
              the  cursor.   Usually, typing ^D would generate a standard list
              of completions for the word on the command line, and show  that.
              With  _oldlist,  it  will  instead  show the list of corrections
              already generated.

              As another example  consider  the  _match  completer:  with  the
              insert-unambiguous  style set to `true' it inserts only a common
              prefix string, if there is any.  However, this may remove  parts
              of  the  original pattern, so that further completion could pro-
              duce more matches than on  the  first  attempt.   By  using  the
              _oldlist completer and setting this style to _match, the list of
              matches generated on the first attempt will be used again.

       old-matches
              This is used by the _all_matches completer to decide if  an  old
              list  of matches should be used if one exists.  This is selected
              by one of the `true' values or by the  string  `only'.   If  the
              value  is  `only',  _all_matches  will  only use an old list and
              won't have any effect on the list  of  matches  currently  being
              generated.

              If  this  style  is  set  it  is  generally  unwise  to call the
              _all_matches completer unconditionally.  One possible use is for
              either  this style or the completer style to be defined with the
              -e option to zstyle to make the style conditional.

       old-menu
              This is used by the _oldlist completer.  It  controls  how  menu
              completion  behaves  when a completion has already been inserted
              and the user types a standard completion key such as  TAB.   The
              default  behaviour  of  _oldlist  is that menu completion always
              continues with the existing list of completions.  If this  style
              is  set  to `false', however, a new completion is started if the
              old list was generated by a different completion  command;  this
              is the behaviour without the _oldlist completer.

              For  example, suppose you type ^Xc to generate a list of correc-
              tions, and menu completion is started in one of the usual  ways.
              Usually,  or  with this style set to `false', typing TAB at this
              point would start trying to complete the line as it now appears.
              With _oldlist, it instead continues to cycle through the list of
              corrections.

       original
              This is used by the  _approximate  and  _correct  completers  to
              decide if the original string should be added as a possible com-
              pletion.  Normally, this is done only if there are at least  two
              possible  corrections, but if this style is set to `true', it is
              always added.  Note that the style will  be  examined  with  the
              completer  field  in  the  context  name  set  to correct-num or
              approximate-num, where num is the number  of  errors  that  were
              accepted.

       packageset
              This  style  is  used  when  completing  arguments of the Debian
              `dpkg' program.  It contains an override for the default package
              set for a given context.  For example,

                     zstyle ':completion:*:complete:dpkg:option--status-1:*' \
                                    packageset avail

              causes  available packages, rather than only installed packages,
              to be completed for `dpkg --status'.

       path   The function that completes color names uses this style with the
              colors tag.  The value should be the pathname of a file contain-
              ing color names in the format of an X11 rgb.txt  file.   If  the
              style  is not set but this file is found in one of various stan-
              dard locations it will be used as the default.

       path-completion
              This is used by filename completion.  By default, filename  com-
              pletion  examines  all  components of a path to see if there are
              completions of that component.  For example, /u/b/z can be  com-
              pleted  to  /usr/bin/zsh.   Explicitly  setting  this  style  to
              `false' inhibits this behaviour for path components up to the  /
              before    the    cursor;   this   overrides   the   setting   of
              accept-exact-dirs.

              Even with the style set to `false', it is still possible to com-
              plete  multiple paths by setting the option COMPLETE_IN_WORD and
              moving the cursor back to the first component in the path to  be
              completed.  For example, /u/b/z can be completed to /usr/bin/zsh
              if the cursor is after the /u.

       pine-directory
              If set, specifies the directory containing PINE  mailbox  files.
              There  is no default, since recursively searching this directory
              is inconvenient for anyone who doesn't use PINE.

       ports  A list of Internet service names (network  ports)  to  complete.
              If  this  is  not  set,  service  names  are taken from the file
              `/etc/services'.

       prefix-hidden
              This is used for certain completions which share a  common  pre-
              fix,  for  example command options beginning with dashes.  If it
              is `true', the prefix will not be shown in the list of matches.

              The default value for this style is `false'.

       prefix-needed
              This style is also relevant for matches with  a  common  prefix.
              If  it  is set to `true' this common prefix must be typed by the
              user to generate the matches.

              The style is applicable to the  options,  signals,  jobs,  func-
              tions, and parameters completion tags.

              For  command  options,  this means that the initial `-', `+', or
              `--' must be typed explicitly before option names will  be  com-
              pleted.

              For signals, an initial `-' is required before signal names will
              be completed.

              For jobs, an initial `%' is required before job  names  will  be
              completed.

              For  function  and  parameter  names,  an  initial `_' or `.' is
              required before function or parameter names starting with  those
              characters will be completed.

              The  default  value  for  this style is `false' for function and
              parameter completions, and  `true' otherwise.

       preserve-prefix
              This style is used when completing path names.  Its value should
              be  a pattern matching an initial prefix of the word to complete
              that should be left  unchanged  under  all  circumstances.   For
              example,  on  some  Unices  an initial `//' (double slash) has a
              special meaning; setting this style to the string `//' will pre-
              serve it.  As another example, setting this style to `?:/' under
              Cygwin would allow completion after `a:/...' and so on.

       range  This is used by the _history  completer  and  the  _history_com-
              plete_word bindable command to decide which words should be com-
              pleted.

              If it is a single number, only the last N words from the history
              will be completed.

              If  it  is a range of the form `max:slice', the last slice words
              will be completed; then if that yields  no  matches,  the  slice
              words  before those will be tried and so on.  This process stops
              either when at least one match has been found, or max words have
              been tried.

              The default is to complete all words from the history at once.

       recursive-files
              If  this  style  is set, its value is an array of patterns to be
              tested against `$PWD/': note the trailing  slash,  which  allows
              directories  in  the  pattern  to  be delimited unambiguously by
              including slashes on both sides.  If an ordinary file completion
              fails  and  the  word  on  the  command line does not yet have a
              directory part to its name, the style  is  retrieved  using  the
              same tag as for the completion just attempted, then the elements
              tested against $PWD/ in turn.  If one matches,  then  the  shell
              reattempts completion by prepending the word on the command line
              with each directory in the expansion of **/*(/) in turn.   Typi-
              cally the elements of the style will be set to restrict the num-
              ber of directories beneath the current one to a manageable  num-
              ber, for example `*/.git/*'.

              For example,

                     zstyle ':completion:*' recursive-files '*/zsh/*'

              If  the  current  directory is /home/pws/zsh/Src, then zle_trTAB
              can be completed to Zle/zle_tricky.c.

       regular
              This style is used by the _expand_alias completer  and  bindable
              command.   If  set to `true' (the default), regular aliases will
              be expanded but only in command  position.   If  it  is  set  to
              `false',  regular aliases will never be expanded.   If it is set
              to `always', regular aliases will be expanded  even  if  not  in
              command position.

       rehash If  this  is set when completing external commands, the internal
              list (hash) of commands will be updated for each search by issu-
              ing the rehash command.  There is a speed penalty for this which
              is only likely to be noticeable when  directories  in  the  path
              have slow file access.

       remote-access
              If  set to `false', certain commands will be prevented from mak-
              ing Internet connections to retrieve remote  information.   This
              includes the completion for the CVS command.

              It  is not always possible to know if connections are in fact to
              a remote site, so some may be prevented unnecessarily.

       remove-all-dups
              The _history_complete_word bindable  command  and  the  _history
              completer  use this to decide if all duplicate matches should be
              removed, rather than just consecutive duplicates.

       select-prompt
              If this is set for the default tag, its value will be  displayed
              during  menu  selection (see the menu style above) when the com-
              pletion list does not fit on the screen as a  whole.   The  same
              escapes as for the list-prompt style are understood, except that
              the numbers refer to the match  or  line  the  mark  is  on.   A
              default prompt is used when the value is the empty string.

       select-scroll
              This  style  is  tested for the default tag and determines how a
              completion list is scrolled during a  menu  selection  (see  the
              menu  style  above) when the completion list does not fit on the
              screen as a whole.  If the value is  `0'  (zero),  the  list  is
              scrolled  by  half-screenfuls;  if it is a positive integer, the
              list is scrolled by the given number of lines; if it is a  nega-
              tive number, the list is scrolled by a screenful minus the abso-
              lute value of the given number of  lines.   The  default  is  to
              scroll by single lines.

       separate-sections
              This style is used with the manuals tag when completing names of
              manual pages.  If it is `true', entries for  different  sections
              are  added  separately  using  tag names of the form `manual.X',
              where X is the section number.  When  the  group-name  style  is
              also  in effect, pages from different sections will appear sepa-
              rately.  This style is also used similarly with the words  style
              when completing words for the dict command. It allows words from
              different dictionary databases  to  be  added  separately.   The
              default for this style is `false'.

       show-ambiguity
              If  the zsh/complist module is loaded, this style can be used to
              highlight the first ambiguous character in completion lists. The
              value  is  either  a color indication such as those supported by
              the list-colors style or, with a value of `true', a  default  of
              underlining is selected. The highlighting is only applied if the
              completion display strings correspond to the actual matches.

       show-completer
              Tested whenever a new completer is tried.  If it is `true',  the
              completion system outputs a progress message in the listing area
              showing what completer is being  tried.   The  message  will  be
              overwritten  by  any  output  when  completions are found and is
              removed after completion is finished.

       single-ignored
              This is used by the _ignored completer when there  is  only  one
              match.   If  its  value is `show', the single match will be dis-
              played but not inserted.  If the value is `menu', then the  sin-
              gle  match and the original string are both added as matches and
              menu completion is started, making it easy to select  either  of
              them.

       sort   Many  completion  widgets  call _description at some point which
              decides whether the matches are added sorted or unsorted  (often
              indirectly  via  _wanted  or _requested).  This style can be set
              explicitly to one of the usual `true' or `false'  values  as  an
              override.  If it is not set for the context, the standard behav-
              iour of the calling widget is used.

              The style is tested first against the full context including the
              tag,  and  if  that fails to produce a value against the context
              without the tag.

              If the calling widget explicitly requests unsorted matches, this
              is  usually honoured.  However, the default (unsorted) behaviour
              of completion for the command history may be overridden by  set-
              ting the style to `true'.

              In the _expand completer, if it is set to `true', the expansions
              generated will always be sorted.  If it is set to  `menu',  then
              the  expansions  are only sorted when they are offered as single
              strings but not in the string  containing  all  possible  expan-
              sions.

       special-dirs
              Normally,  the  completion  code  will not produce the directory
              names `.' and `..' as possible completions.  If  this  style  is
              set to `true', it will add both `.' and `..' as possible comple-
              tions; if it is set to `..', only `..' will be added.

              The following example sets special-dirs to `..' when the current
              prefix  is  empty,  is  a single `.', or consists only of a path
              beginning with `../'.  Otherwise the value is `false'.

                     zstyle -e ':completion:*' special-dirs \
                        '[[ $PREFIX = (../)#(|.|..) ]] && reply=(..)'

       squeeze-slashes
              If set to `true', sequences of slashes in  filename  paths  (for
              example  in `foo//bar') will be treated as a single slash.  This
              is the usual behaviour of UNIX paths.  However, by  default  the
              file  completion function behaves as if there were a `*' between
              the slashes.

       stop   If set to `true', the  _history_complete_word  bindable  command
              will  stop  once  when reaching the beginning or end of the his-
              tory.  Invoking _history_complete_word will then wrap around  to
              the  opposite  end  of  the  history.   If  this style is set to
              `false' (the default), _history_complete_word will loop  immedi-
              ately as in a menu completion.

       strip-comments
              If  set  to `true', this style causes non-essential comment text
              to be removed from completion matches.   Currently  it  is  only
              used  when completing e-mail addresses where it removes any dis-
              play name  from  the  addresses,  cutting  them  down  to  plain
              user@host form.

       subst-globs-only
              This  is used by the _expand completer.  If it is set to `true',
              the expansion will only be used if it  resulted  from  globbing;
              hence,  if  expansions  resulted  from the use of the substitute
              style described below, but these were  not  further  changed  by
              globbing, the expansions will be rejected.

              The default for this style is `false'.

       substitute
              This  boolean  style controls whether the _expand completer will
              first try to expand all substitutions in  the  string  (such  as
              `$(...)' and `${...}').

              The default is `true'.

       suffix This  is used by the _expand completer if the word starts with a
              tilde or contains a  parameter  expansion.   If  it  is  set  to
              `true', the word will only be expanded if it doesn't have a suf-
              fix, i.e. if it is something like `~foo' or `$foo'  rather  than
              `~foo/'  or `$foo/bar', unless that suffix itself contains char-
              acters eligible for expansion.  The default for  this  style  is
              `true'.

       tag-order
              This  provides a mechanism for sorting how the tags available in
              a particular context will be used.

              The values for the style are sets of  space-separated  lists  of
              tags.  The tags in each value will be tried at the same time; if
              no match is found, the next value is used.  (See  the  file-pat-
              terns style for an exception to this behavior.)

              For example:

                     zstyle ':completion:*:complete:-command-:*:*' tag-order \
                         'commands functions'

              specifies  that  completion  in  command  position  first offers
              external commands and shell functions.  Remaining tags  will  be
              tried if no completions are found.

              In  addition to tag names, each string in the value may take one
              of the following forms:

              -      If any value consists of only a  hyphen,  then  only  the
                     tags  specified  in the other values are generated.  Nor-
                     mally all tags not explicitly selected are tried last  if
                     the  specified  tags  fail to generate any matches.  This
                     means that a single value consisting  only  of  a  single
                     hyphen turns off completion.

              ! tags...
                     A  string  starting  with  an  exclamation mark specifies
                     names of tags that are not to be used.  The effect is the
                     same  as  if  all other possible tags for the context had
                     been listed.

              tag:label ...
                     Here, tag is one of the standard tags  and  label  is  an
                     arbitrary  name.  Matches are generated as normal but the
                     name label is used in contexts instead of tag.   This  is
                     not useful in words starting with !.

                     If  the  label starts with a hyphen, the tag is prepended
                     to the label to form the name used for lookup.  This  can
                     be  used  to make the completion system try a certain tag
                     more than once, supplying different  style  settings  for
                     each attempt; see below for an example.

              tag:label:description
                     As  before,  but description will replace the `%d' in the
                     value of the format style instead of the default descrip-
                     tion  supplied by the completion function.  Spaces in the
                     description must be quoted  with  a  backslash.   A  `%d'
                     appearing in description is replaced with the description
                     given by the completion function.

              In any of the forms above the tag may be a  pattern  or  several
              patterns  in the form `{pat1,pat2...}'.  In this case all match-
              ing tags will be used except for any  given  explicitly  in  the
              same string.

              One use of these features is to try one tag more than once, set-
              ting other styles differently on each attempt, but still to  use
              all the other tags without having to repeat them all.  For exam-
              ple, to make completion of function names  in  command  position
              ignore  all the completion functions starting with an underscore
              the first time completion is tried:

                     zstyle ':completion:*:*:-command-:*:*' tag-order \
                         'functions:-non-comp *' functions
                     zstyle ':completion:*:functions-non-comp' \
                         ignored-patterns '_*'

              On the first attempt, all tags will be offered but the functions
              tag  will  be  replaced by functions-non-comp.  The ignored-pat-
              terns style is set for this tag to  exclude  functions  starting
              with  an  underscore.  If there are no matches, the second value
              of the tag-order style is used which completes  functions  using
              the  default  tag,  this  time presumably including all function
              names.

              The matches for one tag can be split into different groups.  For
              example:

                     zstyle ':completion:*' tag-order \
                         'options:-long:long\ options
                          options:-short:short\ options
                          options:-single-letter:single\ letter\ options'
                     zstyle ':completion:*:options-long' \
                          ignored-patterns '[-+](|-|[^-]*)'
                     zstyle ':completion:*:options-short' \
                          ignored-patterns '--*' '[-+]?'
                     zstyle ':completion:*:options-single-letter' \
                          ignored-patterns '???*'

              With  the  group-names  style  set, options beginning with `--',
              options beginning with a single `-' or `+' but containing multi-
              ple  characters,  and single-letter options will be displayed in
              separate groups with different descriptions.

              Another use of patterns is to try multiple match  specifications
              one after another.  The matcher-list style offers something sim-
              ilar, but it is tested very early in the completion  system  and
              hence  can't  be  set  for single commands nor for more specific
              contexts.  Here is how to  try  normal  completion  without  any
              match specification and, if that generates no matches, try again
              with case-insensitive matching, restricting the effect to  argu-
              ments of the command foo:

                     zstyle ':completion:*:*:foo:*:*' tag-order '*' '*:-case'
                     zstyle ':completion:*-case' matcher 'm:{a-z}={A-Z}'

              First,  all the tags offered when completing after foo are tried
              using the normal tag name.  If that generates  no  matches,  the
              second  value  of  tag-order is used, which tries all tags again
              except that this time each has -case appended to  its  name  for
              lookup  of  styles.   Hence  this time the value for the matcher
              style from the second call to zstyle in the example is  used  to
              make completion case-insensitive.

              It  is  possible to use the -e option of the zstyle builtin com-
              mand to specify conditions for the use of particular tags.   For
              example:

                     zstyle -e '*:-command-:*' tag-order '
                         if [[ -n $PREFIX$SUFFIX ]]; then
                           reply=( )
                         else
                           reply=( - )
                         fi'

              Completion  in  command  position  will be attempted only if the
              string typed so far is not empty.  This is tested using the PRE-
              FIX  special  parameter;  see  zshcompwid  for  a description of
              parameters which are special inside completion widgets.  Setting
              reply to an empty array provides the default behaviour of trying
              all tags at once; setting it  to  an  array  containing  only  a
              hyphen  disables  the  use  of all tags and hence of all comple-
              tions.

              If no tag-order style  has  been  defined  for  a  context,  the
              strings  `(|*-)argument-*  (|*-)option-*  values'  and `options'
              plus all tags offered by the completion function will be used to
              provide  a  sensible  default  behavior  that  causes  arguments
              (whether normal command arguments or arguments of options) to be
              completed before option names for most commands.

       urls   This  is used together with the urls tag by functions completing
              URLs.

              If the value consists of more than one string, or  if  the  only
              string  does  not name a file or directory, the strings are used
              as the URLs to complete.

              If the value contains only one string which is  the  name  of  a
              normal  file  the  URLs are taken from that file (where the URLs
              may be separated by white space or newlines).

              Finally, if the only string in the value names a directory,  the
              directory  hierarchy  rooted at this directory gives the comple-
              tions.  The top  level  directory  should  be  the  file  access
              method,  such  as  `http', `ftp', `bookmark' and so on.  In many
              cases the next level of directories will  be  a  filename.   The
              directory hierarchy can descend as deep as necessary.

              For example,

                     zstyle ':completion:*' urls ~/.urls
                     mkdir -p ~/.urls/ftp/ftp.zsh.org/pub

              allows   completion   of   all   the   components   of  the  URL
              ftp://ftp.zsh.org/pub after suitable commands such as `netscape'
              or  `lynx'.   Note,  however,  that access methods and files are
              completed separately, so if the hosts style is set hosts can  be
              completed without reference to the urls style.

              See the description in the function _urls itself for more infor-
              mation (e.g. `more $^fpath/_urls(N)').

       use-cache
              If this is set, the completion caching layer  is  activated  for
              any   completions   which   use   it   (via   the  _store_cache,
              _retrieve_cache, and _cache_invalid functions).   The  directory
              containing  the  cache  files can be changed with the cache-path
              style.

       use-compctl
              If this style is set to a string not equal to false, 0, no,  and
              off, the completion system may use any completion specifications
              defined with the compctl  builtin  command.   If  the  style  is
              unset,  this  is  done only if the zsh/compctl module is loaded.
              The string may also contain the substring `first' to use comple-
              tions  defined with `compctl -T', and the substring `default' to
              use the completion defined with `compctl -D'.

              Note that this is only intended to smooth  the  transition  from
              compctl  to  the  new completion system and may disappear in the
              future.

              Note also that the definitions from compctl will only be used if
              there  is  no  specific  completion  function for the command in
              question.  For example, if there is a function _foo to  complete
              arguments  to the command foo, compctl will never be invoked for
              foo.  However, the compctl version will be  tried  if  foo  only
              uses default completion.

       use-ip By default, the function _hosts that completes host names strips
              IP addresses from entries read from host databases such  as  NIS
              and  ssh  files.   If this style is `true', the corresponding IP
              addresses can be completed as well.  This style is  not  use  in
              any  context  where the hosts style is set; note also it must be
              set before the cache of host names is generated  (typically  the
              first completion attempt).

       users  This  may  be set to a list of usernames to be completed.  If it
              is not set all usernames will be completed.  Note that if it  is
              set  only  that list of users will be completed; this is because
              on some systems querying all users can take a prohibitive amount
              of time.

       users-hosts
              The  values  of  this style should be of the form `user@host' or
              `user:host'. It is used for commands that need  pairs  of  user-
              and hostnames.  These commands will complete usernames from this
              style (only), and will restrict subsequent  hostname  completion
              to  hosts  paired  with  that  user  in one of the values of the
              style.

              It is possible to group values for sets of commands which  allow
              a remote login, such as rlogin and ssh, by using the my-accounts
              tag.  Similarly, values for sets of commands which usually refer
              to the accounts of other people, such as talk and finger, can be
              grouped by using the other-accounts tag.  More  ambivalent  com-
              mands may use the accounts tag.

       users-hosts-ports
              Like  users-hosts but used for commands like telnet and contain-
              ing strings of the form `user@host:port'.

       verbose
              If set, as it is by default, the completion listing is more ver-
              bose.  In particular many commands show descriptions for options
              if this style is `true'.

       word   This is used by the _list completer, which prevents  the  inser-
              tion  of  completions until a second completion attempt when the
              line has not changed.  The normal way of finding out if the line
              has  changed  is  to compare its entire contents between the two
              occasions.  If this style is `true', the comparison  is  instead
              performed only on the current word.  Hence if completion is per-
              formed on another word with the same contents,  completion  will
              not be delayed.

CONTROL FUNCTIONS
       The initialization script compinit redefines all the widgets which per-
       form completion to call the supplied  widget  function  _main_complete.
       This function acts as a wrapper calling the so-called `completer' func-
       tions that generate matches.  If _main_complete is  called  with  argu-
       ments, these are taken as the names of completer functions to be called
       in the order given.  If no arguments are given, the set of functions to
       try is taken from the completer style.  For example, to use normal com-
       pletion and correction if that doesn't generate any matches:

              zstyle ':completion:*' completer _complete _correct

       after calling compinit. The default value for this style is  `_complete
       _ignored',  i.e. normally only ordinary completion is tried, first with
       the effect of the ignored-patterns style  and  then  without  it.   The
       _main_complete  function  uses the return status of the completer func-
       tions to decide if other completers should be called.   If  the  return
       status  is  zero,  no other completers are tried and the _main_complete
       function returns.

       If the first argument to _main_complete is a single hyphen,  the  argu-
       ments  will  not  be taken as names of completers.  Instead, the second
       argument gives a name to use in the completer field of the context  and
       the other arguments give a command name and arguments to call to gener-
       ate the matches.

       The following completer functions are contained  in  the  distribution,
       although  users may write their own.  Note that in contexts the leading
       underscore is stripped, for example basic completion  is  performed  in
       the context `:completion::complete:...'.

       _all_matches
              This  completer  can  be  used to add a string consisting of all
              other matches.  As it influences later completers it must appear
              as  the first completer in the list.  The list of all matches is
              affected by the avoid-completer and old-matches styles described
              above.

              It may be useful to use the _generic function described below to
              bind _all_matches to its own keystroke, for example:

                     zle -C all-matches complete-word _generic
                     bindkey '^Xa' all-matches
                     zstyle ':completion:all-matches:*' old-matches only
                     zstyle ':completion:all-matches::::' completer _all_matches

              Note that this does not generate completions by  itself:   first
              use  any  of  the  standard ways of generating a list of comple-
              tions, then use ^Xa to show all matches.  It is possible instead
              to  add  a  standard  completer to the list and request that the
              list of all matches should be directly inserted:

                     zstyle ':completion:all-matches::::' completer \
                            _all_matches _complete
                     zstyle ':completion:all-matches:*' insert true

              In this case the old-matches style should not be set.

       _approximate
              This is similar to the basic _complete completer but allows  the
              completions  to  undergo  corrections.   The  maximum  number of
              errors can  be  specified  by  the  max-errors  style;  see  the
              description of approximate matching in zshexpn(1) for how errors
              are counted.  Normally this completer will only be  tried  after
              the normal _complete completer:

                     zstyle ':completion:*' completer _complete _approximate

              This  will give correcting completion if and only if normal com-
              pletion yields no possible completions.  When corrected  comple-
              tions  are found, the completer will normally start menu comple-
              tion allowing you to cycle through these strings.

              This completer uses the tags corrections and original when  gen-
              erating  the  possible corrections and the original string.  The
              format style for the former may contain the additional sequences
              `%e'  and  `%o'  which  will be replaced by the number of errors
              accepted to generate the corrections and  the  original  string,
              respectively.

              The  completer  progressively  increases  the  number  of errors
              allowed up to the limit by the max-errors style, hence if a com-
              pletion  is found with one error, no completions with two errors
              will be shown, and so on.  It modifies the completer name in the
              context  to  indicate  the  number of errors being tried: on the
              first try the completer field contains `approximate-1',  on  the
              second try `approximate-2', and so on.

              When _approximate is called from another function, the number of
              errors to accept may be passed with the -a option.  The argument
              is  in  the  same  format  as  the  max-errors style, all in one
              string.

              Note that this completer (and the _correct  completer  mentioned
              below)  can  be quite expensive to call, especially when a large
              number of errors are allowed.  One way to avoid this is  to  set
              up  the  completer  style  using the -e option to zstyle so that
              some completers are only used when  completion  is  attempted  a
              second time on the same string, e.g.:

                     zstyle -e ':completion:*' completer '
                       if [[ $_last_try != "$HISTNO$BUFFER$CURSOR" ]]; then
                         _last_try="$HISTNO$BUFFER$CURSOR"
                         reply=(_complete _match _prefix)
                       else
                         reply=(_ignored _correct _approximate)
                       fi'

              This uses the HISTNO parameter and the BUFFER and CURSOR special
              parameters that are available inside zle and completion  widgets
              to  find  out  if the command line hasn't changed since the last
              time completion was tried.  Only then are the _ignored, _correct
              and _approximate completers called.

       _canonical_paths  [ -A var ] [ -N ] [ -MJV12nfX ] tag descr [ paths ...
       ]
              This completion function completes all paths given  to  it,  and
              also  tries to offer completions which point to the same file as
              one of the paths given (relative path when an absolute  path  is
              given,  and  vice versa; when ..'s are present in the word to be
              completed; and some paths got from symlinks).

              -A, if specified, takes the paths from the array variable speci-
              fied.  Paths  can also be specified on the command line as shown
              above.  -N, if  specified,  prevents  canonicalizing  the  paths
              given before using them for completion, in case they are already
              so. The options -M, -J, -V, -1, -2, -n, -F,  -X  are  passed  to
              compadd.

              See _description for a description of tag and descr.

       _cmdambivalent
              Completes the remaining positional arguments as an external com-
              mand.  The external command and its arguments are  completed  as
              separate  arguments  (in  a  manner  appropriate  for completing
              /usr/bin/env) if there are  two  or  more  remaining  positional
              arguments  on  the  command line, and as a quoted command string
              (in the manner of system(...)) otherwise.  See  also  _cmdstring
              and _precommand.

              This function takes no arguments.

       _cmdstring
              Completes  an external command as a single argument, as for sys-
              tem(...).

       _complete
              This completer generates all  possible  completions  in  a  con-
              text-sensitive  manner, i.e. using the settings defined with the
              compdef function explained above and the current settings of all
              special parameters.  This gives the normal completion behaviour.

              To  complete  arguments  of commands, _complete uses the utility
              function _normal, which is in turn responsible for  finding  the
              particular function; it is described below.  Various contexts of
              the form -context- are handled specifically. These are all  men-
              tioned above as possible arguments to the #compdef tag.

              Before  trying  to find a function for a specific context, _com-
              plete checks if the  parameter  `compcontext'  is  set.  Setting
              `compcontext'  allows  the  usual  completion  dispatching to be
              overridden which is useful in places such  as  a  function  that
              uses vared for input. If it is set to an array, the elements are
              taken to be the possible matches which will be  completed  using
              the tag `values' and the description `value'. If it is set to an
              associative array, the keys are used as the possible completions
              and  the  values (if non-empty) are used as descriptions for the
              matches.  If `compcontext' is set to a string containing colons,
              it  should  be of the form `tag:descr:action'.  In this case the
              tag and descr give the tag and description to use and the action
              indicates  what should be completed in one of the forms accepted
              by the _arguments utility function described below.

              Finally, if `compcontext' is set to a string without colons, the
              value  is  taken as the name of the context to use and the func-
              tion defined for that context will be called.  For this purpose,
              there  is  a special context named -command-line- that completes
              whole command lines (commands and their arguments).  This is not
              used  by the completion system itself but is nonetheless handled
              when explicitly called.

       _correct
              Generate corrections, but not completions, for the current word;
              this is similar to _approximate but will not allow any number of
              extra characters at the cursor  as  that  completer  does.   The
              effect  is  similar to spell-checking.  It is based on _approxi-
              mate, but the completer field in the context name is correct.

              For example, with:

                     zstyle ':completion:::::' completer \
                            _complete _correct _approximate
                     zstyle ':completion:*:correct:::' max-errors 2 not-numeric
                     zstyle ':completion:*:approximate:::' max-errors 3 numeric

              correction will accept up to two errors.  If a numeric  argument
              is  given, correction will not be performed, but correcting com-
              pletion will be, and will accept as many errors as given by  the
              numeric  argument.  Without a numeric argument, first correction
              and then correcting completion will be tried, with the first one
              accepting two errors and the second one accepting three errors.

              When  _correct  is called as a function, the number of errors to
              accept may be given following the -a option.  The argument is in
              the same form a values to the accept style, all in one string.

              This  completer  function  is  intended  to  be used without the
              _approximate completer or, as in the example,  just  before  it.
              Using  it  after  the  _approximate  completer  is useless since
              _approximate will at least generate the corrected strings gener-
              ated by the _correct completer -- and probably more.

       _expand
              This  completer function does not really perform completion, but
              instead checks if the word on the command line is  eligible  for
              expansion  and,  if  it is, gives detailed control over how this
              expansion is done.  For this to happen,  the  completion  system
              needs  to  be invoked with complete-word, not expand-or-complete
              (the default binding for TAB), as otherwise the string  will  be
              expanded by the shell's internal mechanism before the completion
              system is started.  Note also this completer  should  be  called
              before the _complete completer function.

              The  tags used when generating expansions are all-expansions for
              the string containing all possible expansions,  expansions  when
              adding  the  possible  expansions as single matches and original
              when adding the original string from the  line.   The  order  in
              which  these strings are generated, if at all, can be controlled
              by the group-order and tag-order styles, as usual.

              The format string for all-expansions and for expansions may con-
              tain  the  sequence  `%o' which will be replaced by the original
              string from the line.

              The kind of expansion to be tried is controlled by  the  substi-
              tute, glob and subst-globs-only styles.

              It is also possible to call _expand as a function, in which case
              the different modes may be selected with options: -s for substi-
              tute, -g for glob and -o for subst-globs-only.

       _expand_alias
              If  the word the cursor is on is an alias, it is expanded and no
              other completers are called.  The types of aliases which are  to
              be  expanded  can  be controlled with the styles regular, global
              and disabled.

              This function is also a bindable command, see the section `Bind-
              able Commands' below.

       _extensions
              If  the  cursor follows the string `*.', filename extensions are
              completed. The extensions are taken from files in current direc-
              tory  or  a  directory specified at the beginning of the current
              word. For exact matches, completion  continues  to  allow  other
              completers  such  as _expand to expand the pattern. The standard
              add-space and prefix-hidden styles are observed.

       _external_pwds
              Completes current directories of other zsh  processes  belonging
              to the current user.

              This  is intended to be used via _generic, bound to a custom key
              combination. Note that pattern matching is enabled  so  matching
              is performed similar to how it works with the _match completer.

       _history
              Complete  words  from  the  shell's command  history.  This com-
              pleter can be controlled by the remove-all-dups, and sort styles
              as for the _history_complete_word bindable command, see the sec-
              tion `Bindable Commands' below and the section `Completion  Sys-
              tem Configuration' above.

       _ignored
              The  ignored-patterns  style  can  be  set to a list of patterns
              which are compared against possible completions;  matching  ones
              are  removed.   With  this  completer those matches can be rein-
              stated, as if no ignored-patterns style were set.  The completer
              actually generates its own list of matches; which completers are
              invoked is determined in the same way as for  the  _prefix  com-
              pleter.  The single-ignored style is also available as described
              above.

       _list  This completer allows the insertion of  matches  to  be  delayed
              until  completion is attempted a second time without the word on
              the line being changed.  On the first attempt, only the list  of
              matches  will  be shown.  It is affected by the styles condition
              and word, see  the  section  `Completion  System  Configuration'
              above.

       _match This  completer  is intended to be used after the _complete com-
              pleter.  It behaves similarly but the string on the command line
              may be a pattern to match against trial completions.  This gives
              the effect of the GLOB_COMPLETE option.

              Normally completion will be performed by taking the pattern from
              the  line,  inserting a `*' at the cursor position and comparing
              the resulting pattern with the possible  completions  generated.
              This  can  be  modified  with the match-original style described
              above.

              The generated matches will  be  offered  in  a  menu  completion
              unless  the  insert-unambiguous  style is set to `true'; see the
              description above for other options for this style.

              Note that matcher specifications defined globally or used by the
              completion  functions (the styles matcher-list and matcher) will
              not be used.

       _menu  This completer was written as simple example  function  to  show
              how  menu  completion  can be enabled in shell code. However, it
              has the notable effect of disabling menu selection which can  be
              useful  with  _generic  based  widgets. It should be used as the
              first completer in the list.  Note that this is  independent  of
              the  setting  of the MENU_COMPLETE option and does not work with
              the other menu completion widgets such as reverse-menu-complete,
              or accept-and-menu-complete.

       _oldlist
              This  completer  controls  how  the  standard completion widgets
              behave when there is an existing list of completions  which  may
              have  been  generated  by  a  special  completion  (i.e. a sepa-
              rately-bound completion command).  It allows the  ordinary  com-
              pletion  keys  to  continue  to use the list of completions thus
              generated, instead of producing a new list of  ordinary  contex-
              tual  completions.   It  should appear in the list of completers
              before any of the widgets which generate matches.  It  uses  two
              styles:  old-list and old-menu, see the section `Completion Sys-
              tem Configuration' above.

       _precommand
              Complete an external command in word-separated arguments, as for
              exec and /usr/bin/env.

       _prefix
              This  completer  can  be  used to try completion with the suffix
              (everything after the cursor) ignored.  In other words, the suf-
              fix  will  not be considered to be part of the word to complete.
              The effect is similar to the expand-or-complete-prefix command.

              The completer style is used to decide which other completers are
              to  be  called to generate matches.  If this style is unset, the
              list of completers set  for  the  current  context  is  used  --
              except,  of  course, the _prefix completer itself.  Furthermore,
              if this completer appears more than once in  the  list  of  com-
              pleters  only  those  completers  not  already tried by the last
              invocation of _prefix will be called.

              For example, consider this global completer style:

                     zstyle ':completion:*' completer \
                         _complete _prefix _correct _prefix:foo

              Here, the _prefix completer tries normal completion but ignoring
              the  suffix.   If that doesn't generate any matches, and neither
              does the call to the _correct completer after it,  _prefix  will
              be called a second time and, now only trying correction with the
              suffix ignored.  On the second invocation the completer part  of
              the context appears as `foo'.

              To use _prefix as the last resort and try only normal completion
              when it is invoked:

                     zstyle ':completion:*' completer _complete ... _prefix
                     zstyle ':completion::prefix:*' completer _complete

              The add-space style is also respected.  If it is set  to  `true'
              then  _prefix  will insert a space between the matches generated
              (if any) and the suffix.

              Note that this completer is only useful if the  COMPLETE_IN_WORD
              option is set; otherwise, the cursor will be moved to the end of
              the current word before the completion code is called and  hence
              there will be no suffix.

       _user_expand
              This  completer  behaves  similarly to the _expand completer but
              instead  performs  expansions  defined  by  users.   The  styles
              add-space  and sort styles specific to the _expand completer are
              usable with _user_expand in addition  to  other  styles  handled
              more generally by the completion system.  The tag all-expansions
              is also available.

              The expansion depends  on  the  array  style  user-expand  being
              defined  for  the current context; remember that the context for
              completers is less specific than that for contextual  completion
              as  the  full  context has not yet been determined.  Elements of
              the array may have one of the following forms:

              $hash

                     hash is the name of an associative array.  Note  this  is
                     not  a  full  parameter  expression, merely a $, suitably
                     quoted to prevent immediate expansion,  followed  by  the
                     name  of  an  associative  array.  If the trial expansion
                     word matches a key in hash, the  resulting  expansion  is
                     the corresponding value.
              _func

                     _func  is  the  name  of a shell function whose name must
                     begin with _ but is not otherwise special to the  comple-
                     tion  system.  The function is called with the trial word
                     as an argument.  If the word is to be expanded, the func-
                     tion  should set the array reply to a list of expansions.
                     Optionally, it can set REPLY to a word that will be  used
                     as  a  description for the set of expansions.  The return
                     status of the function is irrelevant.
BINDABLE COMMANDS
       In addition to the context-dependent completions  provided,  which  are
       expected to work in an intuitively obvious way, there are a few widgets
       implementing special behaviour which can be bound separately  to  keys.
       The following is a list of these and their default bindings.

       _bash_completions
              This  function  is  used by two widgets, _bash_complete-word and
              _bash_list-choices.  It exists  to  provide  compatibility  with
              completion  bindings in bash.  The last character of the binding
              determines what is completed: `!', command names; `$',  environ-
              ment  variables;  `@',  host  names;  `/',  file names; `~' user
              names.  In bash, the binding preceded by `\e' gives  completion,
              and  preceded  by `^X' lists options.  As some of these bindings
              clash with standard zsh bindings, only `\e~' and `^X~' are bound
              by  default.   To add the rest, the following should be added to
              .zshrc after compinit has been run:

                     for key in '!' '$' '@' '/' '~'; do
                       bindkey "\e$key" _bash_complete-word
                       bindkey "^X$key" _bash_list-choices
                     done

              This includes the bindings for `~' in  case  they  were  already
              bound  to  something else; the completion code does not override
              user bindings.

       _correct_filename (^XC)
              Correct the filename path at the cursor position.  Allows up  to
              six  errors in the name.  Can also be called with an argument to
              correct a filename path, independently of zle; the correction is
              printed on standard output.

       _correct_word (^Xc)
              Performs correction of the current argument using the usual con-
              textual completions as possible choices. This stores the  string
              `correct-word'  in  the  function  field of the context name and
              then calls the _correct completer.

       _expand_alias (^Xa)
              This function can be used as a completer and as a bindable  com-
              mand.   It  expands the word the cursor is on if it is an alias.
              The types of alias expanded can be controlled  with  the  styles
              regular, global and disabled.

              When  used as a bindable command there is one additional feature
              that can be selected by setting the complete  style  to  `true'.
              In  this  case,  if  the  word  is  not  the  name  of an alias,
              _expand_alias tries to complete the word to a  full  alias  name
              without  expanding  it.  It leaves the cursor directly after the
              completed word so that invoking  _expand_alias  once  more  will
              expand the now-complete alias name.

       _expand_word (^Xe)
              Performs expansion on the current word:  equivalent to the stan-
              dard expand-word  command,  but  using  the  _expand  completer.
              Before  calling  it, the function field of the context is set to
              `expand-word'.

       _generic
              This function is not defined  as  a  widget  and  not  bound  by
              default.   However,  it  can be used to define a widget and will
              then store the name of the widget in the function field  of  the
              context and call the completion system.  This allows custom com-
              pletion widgets with their own  set  of  style  settings  to  be
              defined  easily.   For example, to define a widget that performs
              normal completion and starts menu selection:

                     zle -C foo complete-word _generic
                     bindkey '...' foo
                     zstyle ':completion:foo:*' menu yes select=1

              Note in particular that the completer style may be set  for  the
              context in order to change the set of functions used to generate
              possible matches.  If _generic is called with  arguments,  those
              are  passed  through to _main_complete as the list of completers
              in place of those defined by the completer style.

       _history_complete_word (\e/)
              Complete words from the shell's command history. This  uses  the
              list, remove-all-dups, sort, and stop styles.

       _most_recent_file (^Xm)
              Complete  the  name  of the most recently modified file matching
              the pattern on the command line (which may be blank).  If  given
              a  numeric  argument  N, complete the Nth most recently modified
              file.  Note the completion, if any, is always unique.

       _next_tags (^Xn)
              This command alters the set of matches used to that for the next
              tag,  or  set of tags, either as given by the tag-order style or
              as set by default; these matches would otherwise not  be  avail-
              able.   Successive  invocations of the command cycle through all
              possible sets of tags.

       _read_comp (^X^R)
              Prompt the user for a string, and use that to perform completion
              on  the  current  word.   There  are  two  possibilities for the
              string.  First, it can be a set  of  words  beginning  `_',  for
              example  `_files  -/', in which case the function with any argu-
              ments will be called to generate the  completions.   Unambiguous
              parts of the function name will be completed automatically (nor-
              mal completion is not available at this point) until a space  is
              typed.

              Second, any other string will be passed as a set of arguments to
              compadd and should hence be an expression specifying what should
              be completed.

              A  very  restricted  set  of  editing commands is available when
              reading the string:  `DEL' and `^H' delete the  last  character;
              `^U'  deletes  the  line,  and `^C' and `^G' abort the function,
              while `RET' accepts the completion.  Note  the  string  is  used
              verbatim  as  a  command  line,  so  arguments must be quoted in
              accordance with standard shell rules.

              Once a string has been read, the next call  to  _read_comp  will
              use  the existing string instead of reading a new one.  To force
              a new string to be read, call _read_comp with  a  numeric  argu-
              ment.

       _complete_debug (^X?)
              This widget performs ordinary completion, but captures in a tem-
              porary file a trace of the shell commands executed by  the  com-
              pletion  system.   Each completion attempt gets its own file.  A
              command to view each of these files is pushed  onto  the  editor
              buffer stack.

       _complete_help (^Xh)
              This  widget  displays  information about the context names, the
              tags, and the completion functions used when completing  at  the
              current  cursor position. If given a numeric argument other than
              1 (as in `ESC-2 ^Xh'), then the styles used and the contexts for
              which they are used will be shown, too.

              Note  that  the  information  about styles may be incomplete; it
              depends on the information available from the  completion  func-
              tions  called,  which  in  turn  is determined by the user's own
              styles and other settings.

       _complete_help_generic
              Unlike other commands listed here, this must  be  created  as  a
              normal ZLE widget rather than a completion widget (i.e. with zle
              -N).  It is used for generating help with a widget bound to  the
              _generic widget that is described above.

              If  this widget is created using the name of the function, as it
              is by default, then when executed it will read a  key  sequence.
              This  is expected to be bound to a call to a completion function
              that uses the _generic widget.  That widget  will  be  executed,
              and  information  provided  in  the  same  format that the _com-
              plete_help widget displays for contextual completion.

              If the widget's name contains debug, for example if it  is  cre-
              ated as `zle -N _complete_debug_generic _complete_help_generic',
              it will read and execute the keystring for a generic  widget  as
              before, but then generate debugging information as done by _com-
              plete_debug for contextual completion.

              If the widget's  name  contains  noread,  it  will  not  read  a
              keystring  but  instead  arrange  that the next use of a generic
              widget run in the same shell will have the effect  as  described
              above.

              The    widget    works    by   setting   the   shell   parameter
              ZSH_TRACE_GENERIC_WIDGET which is read by  _generic.   Unsetting
              the parameter cancels any pending effect of the noread form.

              For example, after executing the following:

                     zle -N _complete_debug_generic _complete_help_generic
                     bindkey '^x:' _complete_debug_generic

              typing `C-x :' followed by the key sequence for a generic widget
              will cause trace output for that widget to be saved to a file.

       _complete_tag (^Xt)
              This widget completes symbol tags created by the etags or  ctags
              programmes (note there is no connection with the completion sys-
              tem's tags) stored in a file TAGS, in the format used by  etags,
              or  tags,  in the format created by ctags.  It will look back up
              the path hierarchy for the first occurrence of either  file;  if
              both  exist,  the  file  TAGS is preferred.  You can specify the
              full path to a TAGS or tags file by setting the parameter $TAGS-
              FILE  or  $tagsfile  respectively.  The corresponding completion
              tags used are etags and vtags, after emacs and vi respectively.

UTILITY FUNCTIONS
       Descriptions follow for utility functions that may be useful when writ-
       ing  completion  functions.   If functions are installed in subdirecto-
       ries, most of these reside in the Base subdirectory.  Like the  example
       functions  for commands in the distribution, the utility functions gen-
       erating matches all follow the convention of returning status  zero  if
       they  generated  completions  and  non-zero  if no matching completions
       could be added.

       _absolute_command_paths
              This function completes  external  commands  as  absolute  paths
              (unlike  _command_names -e which completes their basenames).  It
              takes no arguments.

       _all_labels [ -x ] [ -12VJ ] tag name descr [ command arg ... ]
              This is a  convenient  interface  to  the  _next_label  function
              below,  implementing  the loop shown in the _next_label example.
              The command  and  its  arguments  are  called  to  generate  the
              matches.  The options stored in the parameter name will automat-
              ically be inserted into the args passed to  the  command.   Nor-
              mally,  they  are  put directly after the command, but if one of
              the args is a single hyphen, they are inserted  directly  before
              that.   If  the  hyphen is the last argument, it will be removed
              from the argument list  before  the  command  is  called.   This
              allows  _all_labels  to  be  used  in almost all cases where the
              matches can be generated by a single call to the compadd builtin
              command or by a call to one of the utility functions.

              For example:

                     local expl
                     ...
                     if _requested foo; then
                       ...
                       _all_labels foo expl '...' compadd ... - $matches
                     fi

              Will complete the strings from the matches parameter, using com-
              padd with additional options which  will  take  precedence  over
              those generated by _all_labels.

       _alternative [ -O name ] [ -C name ] spec ...
              This  function is useful in simple cases where multiple tags are
              available.  Essentially  it  implements  a  loop  like  the  one
              described for the _tags function below.

              The  tags to use and the action to perform if a tag is requested
              are  described  using  the  specs  which  are   of   the   form:
              `tag:descr:action'.  The tags are offered using _tags and if the
              tag is requested, the action is executed with the given descrip-
              tion  descr.   The  actions are those accepted by the _arguments
              function (described below), excluding the `->state'  and  `=...'
              forms.

              For example, the action may be a simple function call:

                     _alternative \
                         'users:user:_users' \
                         'hosts:host:_hosts'

              offers usernames and hostnames as possible matches, generated by
              the _users and _hosts functions respectively.

              Like _arguments, this function uses _all_labels to  execute  the
              actions,  which  will  loop over all sets of tags.  Special han-
              dling is only required if there is an additional valid tag,  for
              example inside a function called from _alternative.

              The  option  `-O  name' is used in the same way as by the _argu-
              ments function.  In other words, the elements of the name  array
              will be passed to compadd when executing an action.

              Like  _tags  this function supports the -C option to give a dif-
              ferent name for the argument context field.


       _arguments [ -nswWCRS ] [ -A pat ] [ -O name ] [ -M matchspec ]
                  [ : ] spec ...
       _arguments [ opt ... ] -- [ -l ] [ -i pats ] [ -s pair ]
                  [ helpspec ...]
              This function can be used to give a complete  specification  for
              completion  for  a  command whose arguments follow standard UNIX
              option and argument conventions.

              Options Overview

              Options to _arguments itself must be in separate words, i.e.  -s
              -w,  not  -sw.   The options are followed by specs that describe
              options and arguments of the analyzed command.  To avoid ambigu-
              ity,  all options to _arguments itself may be separated from the
              spec forms by a single colon.

              The `--' form is used to intuit spec forms from the help  output
              of the command being analyzed, and is described in detail below.
              The opts for the `--' form are otherwise the same options as the
              first  form.  Note that `-s' following `--' has a distinct mean-
              ing from `-s' preceding `--', and both may appear.

              The option switches -s, -S, -A, -w, and -W affect how _arguments
              parses  the analyzed command line's options.  These switches are
              useful for commands with standard argument parsing.

              The options of _arguments have the following meanings:

              -n     With this option, _arguments sets the  parameter  NORMARG
                     to  the  position  of  the  first  normal argument in the
                     $words array, i.e. the position  after  the  end  of  the
                     options.   If that argument has not been reached, NORMARG
                     is set to -1.  The caller should  declare  `integer  NOR-
                     MARG' if the -n option is passed; otherwise the parameter
                     is not used.

              -s     Enable option stacking for single-letter options, whereby
                     multiple  single-letter  options  may  be combined into a
                     single word.  For example, the two options `-x' and  `-y'
                     may  be  combined  into a single word `-xy'.  By default,
                     every word corresponds to a single option name (`-xy'  is
                     a single option named `xy').

                     Options  beginning  with a single hyphen or plus sign are
                     eligible for stacking; words beginning with  two  hyphens
                     are not.

                     Note  that  -s after -- has a different meaning, which is
                     documented in the segment entitled `Deriving  spec  forms
                     from the help output'.

              -w     In combination with -s, allow option stacking even if one
                     or more of the options take arguments.  For  example,  if
                     -x  takes an argument, with no -s, `-xy' is considered as
                     a single (unhandled) option; with -s, -xy  is  an  option
                     with  the  argument  `y'; with both -s and -w, -xy is the
                     option -x and the option -y with arguments to -x (and  to
                     -y,  if  it  takes arguments) still to come in subsequent
                     words.

              -W     This option takes -w a stage further:  it is possible  to
                     complete  single-letter  options  even  after an argument
                     that occurs in the same word.  However, it depends on the
                     action performed whether options will really be completed
                     at this point.  For more control, use a utility  function
                     like _guard as part of the action.

              -C     Modify the curcontext parameter for an action of the form
                     `->state'.  This is discussed in detail below.

              -R     Return status 300 instead of zero when a $state is to  be
                     handled, in the `->string' syntax.

              -S     Do  not  complete  options  after a `--' appearing on the
                     line, and ignore the `--'.  For example, with -S, in  the
                     line

                            foobar -x -- -y

                     the  `-x' is considered an option, the `-y' is considered
                     an argument, and the `--' is considered to be neither.

              -A pat Do not complete options after the first non-option  argu-
                     ment  on the line.  pat is a pattern matching all strings
                     which are not to be taken as arguments.  For example,  to
                     make  _arguments  stop completing options after the first
                     normal argument, but ignoring all strings starting with a
                     hyphen  even if they are not described by one of the opt-
                     specs, the form is `-A "-*"'.

              -O name
                     Pass the elements of the array name as arguments to func-
                     tions  called  to  execute actions.  This is discussed in
                     detail below.

              -M matchspec
                     Use the  match  specification  matchspec  for  completing
                     option  names  and  values.  The default matchspec allows
                     partial word completion after `_' and `-', such  as  com-
                     pleting `-f-b' to `-foo-bar'.  The default matchspec is:
                     r:|[_-]=* r:|=*

              specs: overview

              Each of the following forms is a spec describing individual sets
              of options or arguments on the command line being analyzed.

              n:message:action
              n::message:action
                     This describes the n'th  normal  argument.   The  message
                     will  be  printed  above  the  matches  generated and the
                     action indicates what can be completed in  this  position
                     (see  below).  If there are two colons before the message
                     the argument is optional.  If the message  contains  only
                     white  space,  nothing  will be printed above the matches
                     unless the action adds an explanation string itself.

              :message:action
              ::message:action
                     Similar, but describes the next argument, whatever number
                     that  happens  to  be.  If all arguments are specified in
                     this form in the correct order the numbers  are  unneces-
                     sary.

              *:message:action
              *::message:action
              *:::message:action
                     This  describes  how  arguments (usually non-option argu-
                     ments, those not beginning with - or +) are  to  be  com-
                     pleted  when neither of the first two forms was provided.
                     Any number of arguments can be completed in this fashion.

                     With two colons before the  message,  the  words  special
                     array  and  the CURRENT special parameter are modified to
                     refer only to the normal arguments  when  the  action  is
                     executed or evaluated.  With three colons before the mes-
                     sage they are modified to refer only to the normal  argu-
                     ments covered by this description.

              optspec
              optspec:...
                     This  describes  an option.  The colon indicates handling
                     for one or more arguments to the option;  if  it  is  not
                     present, the option is assumed to take no arguments.

                     The  following  forms  are available for the initial opt-
                     spec, whether or not the option has arguments.

                     *optspec
                            Here optspec is one of the remaining forms  below.
                            This   indicates  the  following  optspec  may  be
                            repeated.  Otherwise if the  corresponding  option
                            is already present on the command line to the left
                            of the cursor it will not be offered again.

                     -optname
                     +optname
                            In the simplest  form  the  optspec  is  just  the
                            option name beginning with a minus or a plus sign,
                            such as `-foo'.  The first argument for the option
                            (if  any)  must follow as a separate word directly
                            after the option.

                            Either of `-+optname' and `+-optname' can be  used
                            to  specify  that  -optname  and +optname are both
                            valid.

                            In all the remaining forms, the leading `-' may be
                            replaced by or paired with `+' in this way.

                     -optname-
                            The   first  argument  of  the  option  must  come
                            directly after the option name in the  same  word.
                            For  example,  `-foo-:...' specifies that the com-
                            pleted  option  and  argument   will   look   like
                            `-fooarg'.

                     -optname+
                            The  first  argument  may appear immediately after
                            optname in the same word, or may appear as a sepa-
                            rate   word   after   the  option.   For  example,
                            `-foo+:...' specifies that  the  completed  option
                            and  argument  will  look like either `-fooarg' or
                            `-foo arg'.

                     -optname=
                            The argument may appear as the next  word,  or  in
                            same  word  as the option name provided that it is
                            separated from it by an equals sign,  for  example
                            `-foo=arg' or `-foo arg'.

                     -optname=-
                            The  argument  to  the option must appear after an
                            equals sign in the same word, and may not be given
                            in the next argument.

                     optspec[explanation]
                            An  explanation  string  may be appended to any of
                            the preceding forms of optspec by enclosing it  in
                            brackets, as in `-q[query operation]'.

                            The  verbose  style  is used to decide whether the
                            explanation strings are displayed with the  option
                            in a completion listing.

                            If  no  bracketed  explanation string is given but
                            the auto-description style is  set  and  only  one
                            argument  is described for this optspec, the value
                            of the style is displayed, with any appearance  of
                            the sequence `%d' in it replaced by the message of
                            the first optarg that  follows  the  optspec;  see
                            below.

                     It  is  possible for options with a literal `+' or `=' to
                     appear, but that character must be  quoted,  for  example
                     `-\+'.

                     Each  optarg  following  an  optspec must take one of the
                     following forms:

                     :message:action
                     ::message:action
                            An argument to the option; message and action  are
                            treated  as  for ordinary arguments.  In the first
                            form, the argument is mandatory, and in the second
                            form it is optional.

                            This  group may be repeated for options which take
                            multiple  arguments.   In   other   words,   :mes-
                            sage1:action1:message2:action2  specifies that the
                            option takes two arguments.

                     :*pattern:message:action
                     :*pattern::message:action
                     :*pattern:::message:action
                            This describes multiple arguments.  Only the  last
                            optarg for an option taking multiple arguments may
                            be given in this form.  If the  pattern  is  empty
                            (i.e.  :*:),  all  the remaining words on the line
                            are to be completed as described  by  the  action;
                            otherwise,  all  the  words  up to and including a
                            word matching the  pattern  are  to  be  completed
                            using the action.

                            Multiple  colons  are  treated  as for the `*:...'
                            forms for ordinary arguments:  when the message is
                            preceded  by  two  colons, the words special array
                            and the CURRENT  special  parameter  are  modified
                            during  the  execution or evaluation of the action
                            to refer only to the words after the option.  When
                            preceded  by  three  colons,  they are modified to
                            refer only to the words covered by  this  descrip-
                            tion.

              Any literal colon in an optname, message, or action must be pre-
              ceded by a backslash, `\:'.

              Each of the forms above may be preceded by a list in parentheses
              of option names and argument numbers.  If the given option is on
              the command line, the options and arguments indicated in  paren-
              theses   will  not  be  offered.   For  example,  `(-two  -three
              1)-one:...' completes the option `-one'; if this appears on  the
              command line, the options -two and -three and the first ordinary
              argument will not be completed after it.  `(-foo):...' specifies
              an  ordinary  argument completion; -foo will not be completed if
              that argument is already present.

              Other items may appear in the list of excluded options to  indi-
              cate  various  other  items  that should not be applied when the
              current specification is matched: a single star (*) for the rest
              arguments  (i.e.  a  specification of the form `*:...'); a colon
              (:) for all normal (non-option-) arguments; and a hyphen (-) for
              all options.  For example, if `(*)' appears before an option and
              the option appears on the command line, the  list  of  remaining
              arguments  (those  shown in the above table beginning with `*:')
              will not be completed.

              To aid in reuse of specifications, it is possible to precede any
              of  the  forms  above  with `!'; then the form will no longer be
              completed, although if the option or  argument  appears  on  the
              command  line  they will be skipped as normal.  The main use for
              this is when the arguments are given by an array, and _arguments
              is  called  repeatedly  for more specific contexts: on the first
              call `_arguments $global_options' is  used,  and  on  subsequent
              calls `_arguments !$^global_options'.

              specs: actions

              In each of the forms above the action determines how completions
              should be generated.  Except for the `->string' form below,  the
              action  will  be executed by calling the _all_labels function to
              process all tag labels.  No special handling of tags  is  needed
              unless a function call introduces a new one.

              The  functions called to execute actions will be called with the
              elements of the array named by the `-O  name'  option  as  argu-
              ments.   This  can be used, for example, to pass the same set of
              options for the compadd builtin to all actions.

              The forms for action are as follows.

               (single unquoted space)
                     This is useful where an argument is required  but  it  is
                     not  possible  or  desirable  to generate matches for it.
                     The message will be displayed but no completions  listed.
                     Note  that  even in this case the colon at the end of the
                     message is needed; it may only be omitted when neither  a
                     message nor an action is given.

              (item1 item2 ...)
                     One of a list of possible matches, for example:

                            :foo:(foo bar baz)

              ((item1\:desc1 ...))
                     Similar to the above, but with descriptions for each pos-
                     sible match.  Note the backslash before the  colon.   For
                     example,

                            :foo:((a\:bar b\:baz))

                     The  matches  will be listed together with their descrip-
                     tions if the description style is set with the values tag
                     in the context.

              ->string
                     In  this  form,  _arguments  processes  the arguments and
                     options and then returns control to the calling  function
                     with  parameters set to indicate the state of processing;
                     the calling function then makes its own arrangements  for
                     generating  completions.   For  example,  functions  that
                     implement a state machine can use this type of action.

                     Where _arguments encounters action in the `->string' for-
                     mat,  it  will  strip all leading and trailing whitespace
                     from string and set the array state to  the  set  of  all
                     strings for which an action is to be performed.  The ele-
                     ments of the array state_descr are  assigned  the  corre-
                     sponding  message  field from each optarg containing such
                     an action.

                     By default and in common with all other well behaved com-
                     pletion  functions,  _arguments returns status zero if it
                     was able to add matches and non-zero otherwise.  However,
                     if the -R option is given, _arguments will instead return
                     a status of 300 to indicate that $state is to be handled.

                     In addition to $state and $state_descr,  _arguments  also
                     sets   the   global   parameters  `context',  `line'  and
                     `opt_args' as described below, and  does  not  reset  any
                     changes made to the special parameters such as PREFIX and
                     words.  This gives the calling  function  the  choice  of
                     resetting  these  parameters  or  propagating  changes in
                     them.

                     A function calling _arguments with at  least  one  action
                     containing  a `->string' must therefore declare appropri-
                     ate local parameters:

                            local context state state_descr line
                            typeset -A opt_args

                     to prevent _arguments from altering the  global  environ-
                     ment.

              {eval-string}
                     A string in braces is evaluated as shell code to generate
                     matches.  If the eval-string itself does not  begin  with
                     an opening parenthesis or brace it is split into separate
                     words before execution.

              = action
                     If the action starts with `= ' (an equals  sign  followed
                     by  a  space), _arguments will insert the contents of the
                     argument field of the current context as  the  new  first
                     element  in  the  words  special  array and increment the
                     value of the CURRENT special  parameter.   This  has  the
                     effect of inserting a dummy word onto the completion com-
                     mand line while not changing the point at  which  comple-
                     tion is taking place.

                     This  is  most  useful  with  one  of the specifiers that
                     restrict the words on  the  command  line  on  which  the
                     action  is  to  operate  (the  two- and three-colon forms
                     above).  One particular use  is  when  an  action  itself
                     causes  _arguments on a restricted range; it is necessary
                     to use this trick to insert an appropriate  command  name
                     into  the  range  for the second call to _arguments to be
                     able to parse the line.

               word...
              word...
                     This covers all forms other than  those  above.   If  the
                     action  starts  with a space, the remaining list of words
                     will be invoked unchanged.

                     Otherwise it will be  invoked  with  some  extra  strings
                     placed  after the first word; these are to be passed down
                     as options to the compadd builtin.  They ensure that  the
                     state specified by _arguments, in particular the descrip-
                     tions of options and arguments, is  correctly  passed  to
                     the  completion  command.  These additional arguments are
                     taken from the array parameter `expl'; this will  be  set
                     up  before executing the action and hence may be referred
                     to inside it, typically  in  an  expansion  of  the  form
                     `$expl[@]' which preserves empty elements of the array.

              During  the  performance  of the action the array `line' will be
              set to the normal arguments from  the  command  line,  i.e.  the
              words from the command line after the command name excluding all
              options and their arguments.  Options are stored in the associa-
              tive  array `opt_args' with option names as keys and their argu-
              ments as the values.  For options that have more than one  argu-
              ment  these  are  given as one string, separated by colons.  All
              colons and backslashes in the original  arguments  are  preceded
              with backslashes.

              The  parameter  `context'  is  set when returning to the calling
              function to perform an action of the form `->string'.  It is set
              to an array of elements corresponding to the elements of $state.
              Each element is a suitable name for the argument  field  of  the
              context: either a string of the form `option-opt-n' for the n'th
              argument of the option -opt, or a  string  of  the  form  `argu-
              ment-n'  for  the  n'th argument.  For `rest' arguments, that is
              those in the list at the end not handled by position, n  is  the
              string `rest'.  For example, when completing the argument of the
              -o option, the name is `option-o-1', while for the second normal
              (non-option-) argument it is `argument-2'.

              Furthermore,  during  the  evaluation  of the action the context
              name in the curcontext parameter is altered to append  the  same
              string that is stored in the context parameter.

              The  option -C tells _arguments to modify the curcontext parame-
              ter for an action of the form `->state'.  This is  the  standard
              parameter  used  to  keep track of the current context.  Here it
              (and not the context array) should be made local to the  calling
              function  to avoid passing back the modified value and should be
              initialised to the current value at the start of the function:

                     local curcontext="$curcontext"

              This is useful where it is not possible for multiple  states  to
              be valid together.

              Grouping Options

              Options  can  be grouped to simplify exclusion lists. A group is
              introduced with `+' followed by a name for the group in the sub-
              sequent  word.  Whole groups can then be referenced in an exclu-
              sion list or a group name can be used  to  disambiguate  between
              two forms of the same option. For example:

                     _arguments \
                         '(group2--x)-a' \
                       + group1 \
                         -m \
                         '(group2)-n' \
                       + group2 \
                         -x -y

              If  the  name  of a group is specified in the form `(name)' then
              only one value from that group will ever be completed; more for-
              mally,  all  specifications  are mutually exclusive to all other
              specifications in  that  group.  This  is  useful  for  defining
              options that are aliases for each other. For example:

                     _arguments \
                         -a -b \
                       + '(operation)' \
                         {-c,--compress}'[compress]' \
                         {-d,--decompress}'[decompress]' \
                         {-l,--list}'[list]'

              If  an  option  in  a  group  appears on the command line, it is
              stored in the associative array `opt_args'  with  'group-option'
              as a key.  In the example above, a key `operation--c' is used if
              the option `-c' is present on the command line.

              Specifying Multiple Sets of Arguments

              It is possible to specify multiple sets of options and arguments
              with  the  sets  separated  by single hyphens. This differs from
              groups in that sets are considered to be mutually  exclusive  of
              each other.

              Specifications  before the first set and from any group are com-
              mon to all sets. For example:

                     _arguments \
                         -a \
                       - set1 \
                         -c \
                       - set2 \
                         -d \
                         ':arg:(x2 y2)'

              This defines two sets.   When  the  command  line  contains  the
              option  `-c',  the `-d' option and the argument will not be con-
              sidered possible completions.  When it contains `-d' or an argu-
              ment,  the  option  `-c' will not be considered.  However, after
              `-a' both sets will still be considered valid.

              As for groups, the name of a set may appear in exclusion  lists,
              either alone or preceding a normal option or argument specifica-
              tion.

              The completion code has to parse the command line separately for
              each set. This can be slow so sets should only be used when nec-
              essary.  A useful alternative is often an  option  specification
              with  rest-arguments  (as in `-foo:*:...'); here the option -foo
              swallows up all remaining arguments as described by  the  optarg
              definitions.

              Deriving spec forms from the help output

              The  option `--' allows _arguments to work out the names of long
              options that support the `--help' option which  is  standard  in
              many GNU commands.  The command word is called with the argument
              `--help' and the output examined for option names.  Clearly,  it
              can  be dangerous to pass this to commands which may not support
              this option as the behaviour of the command is unspecified.

              In addition to options, `_arguments --' will try to  deduce  the
              types   of   arguments  available  for  options  when  the  form
              `--opt=val' is valid.  It is also possible to provide  hints  by
              examining  the  help  text of the command and adding helpspec of
              the form `pattern:message:action'; note  that  other  _arguments
              spec  forms  are  not  used.  The pattern is matched against the
              help text for an option, and  if  it  matches  the  message  and
              action  are  used as for other argument specifiers.  The special
              case of `*:' means both message and action are empty, which  has
              the  effect of causing options having no description in the help
              output to be ordered in listings ahead of options  that  have  a
              description.

              For example:

                     _arguments -- '*\*:toggle:(yes no)' \
                                   '*=FILE*:file:_files' \
                                   '*=DIR*:directory:_files -/' \
                                   '*=PATH*:directory:_files -/'

              Here,  `yes'  and  `no'  will  be  completed  as the argument of
              options whose description ends in a star;  file  names  will  be
              completed  for options that contain the substring `=FILE' in the
              description; and directories will be completed for options whose
              description  contains  `=DIR' or `=PATH'.  The last three are in
              fact the default and so need not be given  explicitly,  although
              it is possible to override the use of these patterns.  A typical
              help text which uses this feature is:

                       -C, --directory=DIR          change to directory DIR

              so that the above specifications will cause  directories  to  be
              completed after `--directory', though not after `-C'.

              Note also that _arguments tries to find out automatically if the
              argument for an option  is  optional.   This  can  be  specified
              explicitly by doubling the colon before the message.

              If the pattern ends in `(-)', this will be removed from the pat-
              tern and the action will be used only directly  after  the  `=',
              not  in the next word.  This is the behaviour of a normal speci-
              fication defined with the form `=-'.

              By default, the command (with the option `--help') is run  after
              resetting  all  the  locale  categories (except for LC_CTYPE) to
              `C'.  If the localized help output is known to work, the  option
              `-l' can be specified after the `_arguments --' so that the com-
              mand is run in the current locale.

              The `_arguments --' can be followed by the option `-i  patterns'
              to give patterns for options which are not to be completed.  The
              patterns can be given as the name of an array parameter or as  a
              literal list in parentheses.  For example,

                     _arguments -- -i \
                         "(--(en|dis)able-FEATURE*)"

              will  cause  completion to ignore the options `--enable-FEATURE'
              and `--disable-FEATURE' (this example is useful with GNU config-
              ure).

              The  `_arguments --' form can also be followed by the option `-s
              pair' to describe option aliases.  The pair consists of  a  list
              of alternating patterns and corresponding replacements, enclosed
              in parens and quoted so that it forms a single argument word  in
              the _arguments call.

              For example, some configure-script help output describes options
              only as `--enable-foo', but the script also accepts the  negated
              form `--disable-foo'.  To allow completion of the second form:

                     _arguments -- -s "((#s)--enable- --disable-)"

              Miscellaneous notes

              Finally,  note  that _arguments generally expects to be the pri-
              mary function handling any completion for which it is used.   It
              may  have side effects which change the treatment of any matches
              added by other functions called after it.  To combine _arguments
              with  other  functions,  those functions should be called either
              before _arguments, as an action within a spec,  or  in  handlers
              for `->state' actions.

              Here is a more general example of the use of _arguments:

                     _arguments '-l+:left border:' \
                                '-format:paper size:(letter A4)' \
                                '*-copy:output file:_files::resolution:(300 600)' \
                                ':postscript file:_files -g \*.\(ps\|eps\)' \
                                '*:page number:'

              This describes three options: `-l', `-format', and `-copy'.  The
              first takes one argument described as `left border' for which no
              completion  will  be  offered  because of the empty action.  Its
              argument may come directly after the `-l' or it may be given  as
              the next word on the line.

              The  `-format'  option  takes  one  argument  in  the next word,
              described as `paper size' for which only  the  strings  `letter'
              and `A4' will be completed.

              The `-copy' option may appear more than once on the command line
              and takes two arguments.  The first is  mandatory  and  will  be
              completed as a filename.  The second is optional (because of the
              second colon before the description `resolution')  and  will  be
              completed from the strings `300' and `600'.

              The  last two descriptions say what should be completed as argu-
              ments.  The first describes the first argument as a  `postscript
              file' and makes files ending in `ps' or `eps' be completed.  The
              last description gives all other arguments the description `page
              numbers' but does not offer completions.

       _cache_invalid cache_identifier
              This  function returns status zero if the completions cache cor-
              responding to the given cache identifier needs  rebuilding.   It
              determines  this  by  looking  up the cache-policy style for the
              current context.  This should provide a function name  which  is
              run  with  the  full path to the relevant cache file as the only
              argument.

              Example:

                     _example_caching_policy () {
                         # rebuild if cache is more than a week old
                         local -a oldp
                         oldp=( "$1"(Nm+7) )
                         (( $#oldp ))
                     }

       _call_function return name [ arg ... ]
              If a function name exists, it is called with the arguments args.
              The  return  argument gives the name of a parameter in which the
              return status from the function name should be stored; if return
              is empty or a single hyphen it is ignored.

              The  return status of _call_function itself is zero if the func-
              tion name exists and was called and non-zero otherwise.

       _call_program [ -l ] [ -p ] tag string ...
              This function provides a mechanism for the user to override  the
              use  of an external command.  It looks up the command style with
              the supplied tag.  If the style is set, its value is used as the
              command to execute.  The strings from the call to _call_program,
              or from the style if set, are concatenated with  spaces  between
              them  and  the resulting string is evaluated.  The return status
              is the return status of the command called.

              By default, the command is run in an environment where  all  the
              locale  categories  (except  for  LC_CTYPE)  are reset to `C' by
              calling the utility function _comp_locale (see  below).  If  the
              option  `-l'  is  given,  the  command  is  run with the current
              locale.

              If the option `-p' is supplied it  indicates  that  the  command
              output  is  influenced by the permissions it is run with. If the
              gain-privileges style is set to true,  _call_program  will  make
              use of commands such as sudo, if present on the command-line, to
              match the permissions to whatever the final command is likely to
              run  under.  When  looking  up  the  gain-privileges and command
              styles, the command component of the  zstyle  context  will  end
              with a slash (`/') followed by the command that would be used to
              gain privileges.

       _combination [ -s pattern ] tag style spec ... field opts ...
              This function is used to complete combinations of  values,   for
              example  pairs  of  hostnames and usernames.  The style argument
              gives the style which defines the pairs; it is looked  up  in  a
              context with the tag specified.

              The style name consists of field names separated by hyphens, for
              example `users-hosts-ports'.  For each  field  for  a  value  is
              already known, a spec of the form `field=pattern' is given.  For
              example, if the command line so far specifies a user `pws',  the
              argument `users=pws' should appear.

              The  next  argument  with no equals sign is taken as the name of
              the field for which completions should be generated  (presumably
              not one of the fields for which the value is known).

              The matches generated will be taken from the value of the style.
              These should contain the possible values for the combinations in
              the  appropriate  order  (users,  hosts,  ports  in  the example
              above).  The values for the different fields  are  separated  by
              colons.   This can be altered with the option -s to _combination
              which specifies a pattern.  Typically this is a character class,
              as for example `-s "[:@]"' in the case of the users-hosts style.
              Each `field=pattern'  specification  restricts  the  completions
              which apply to elements of the style with appropriately matching
              fields.

              If no style with the given name is defined for the given tag, or
              if  none  of  the strings in style's value match, but a function
              name of the required field preceded by an underscore is defined,
              that function will be called to generate the matches.  For exam-
              ple, if there is no `users-hosts-ports' or no matching  hostname
              when  a  host  is required, the function `_hosts' will automati-
              cally be called.

              If the same name is used for more than one field,  in  both  the
              `field=pattern'  and  the  argument  that  gives the name of the
              field to be completed, the number of the  field  (starting  with
              one)  may  be  given after the fieldname, separated from it by a
              colon.

              All arguments after the required field name are passed  to  com-
              padd  when  generating  matches  from the style value, or to the
              functions for the fields if they are called.

       _command_names [ -e | - ]
              This function completes words that are valid  at  command  posi-
              tion:  names  of  aliases, builtins, hashed commands, functions,
              and so on.  With the -e flag,  only  hashed  commands  are  com-
              pleted.  The - flag is ignored.

       _comp_locale
              This  function  resets  all  the  locale  categories  other than
              LC_CTYPE to `C' so that the output from external commands can be
              easily  analyzed  by the completion system. LC_CTYPE retains the
              current value (taking LC_ALL and LANG  into  account),  ensuring
              that  non-ASCII characters in file names are still handled prop-
              erly.

              This function should normally be run only in a subshell, because
              the  new  locale  is  exported to the environment. Typical usage
              would be `$(_comp_locale; command ...)'.

       _completers [ -p ]
              This function completes names of completers.

              -p     Include the leading underscore (`_') in the matches.


       _describe [-12JVx] [ -oO | -t tag ] descr name1 [ name2 ] [ opt ... ]
                 [ -- name1 [ name2 ] [ opt ... ] ... ]
              This function associates completions with descriptions.   Multi-
              ple  groups  separated  by  -- can be supplied, potentially with
              different completion options opts.

              The descr is taken as a string to display above the  matches  if
              the  format style for the descriptions tag is set.  This is fol-
              lowed by one or two names of arrays followed by options to  pass
              to  compadd.   The array name1 contains the possible completions
              with their descriptions in  the  form  `completion:description'.
              Any  literal  colons  in  completion must be quoted with a back-
              slash.  If a name2 is given, it should have the same  number  of
              elements  as  name1; in this case the corresponding elements are
              added as possible completions instead of the completion  strings
              from  name1.   The  completion list will retain the descriptions
              from name1.  Finally, a set of completion options can appear.

              If the option  `-o'  appears  before  the  first  argument,  the
              matches  added will be treated as names of command options (N.B.
              not shell options), typically following a `-', `--'  or  `+'  on
              the  command  line.  In this case _describe uses the prefix-hid-
              den, prefix-needed and verbose styles to find out if the strings
              should be added as completions and if the descriptions should be
              shown.  Without the `-o' option, only the verbose style is  used
              to  decide  how descriptions are shown.  If `-O' is used instead
              of `-o', command options are completed as  above  but  _describe
              will not handle the prefix-needed style.

              With the -t option a tag can be specified.  The default is `val-
              ues' or, if the -o option is given, `options'.

              The options -1, -2, -J, -V, -x are passed to _next_label.

              If selected by the list-grouped style,  strings  with  the  same
              description will appear together in the list.

              _describe uses the _all_labels function to generate the matches,
              so it does not need to appear inside a loop over tag labels.

       _description [ -x ] [ -12VJ ] tag name descr [ spec ... ]
              This function is not to be confused with the previous one; it is
              used  as  a helper function for creating options to compadd.  It
              is buried inside many of the higher level  completion  functions
              and so often does not need to be called directly.

              The  styles listed below are tested in the current context using
              the given tag.  The resulting options for compadd are  put  into
              the  array  named  name  (this is traditionally `expl', but this
              convention is not enforced).  The  description  for  the  corre-
              sponding set of matches is passed to the function in descr.

              The styles tested are: format, hidden, matcher, ignored-patterns
              and group-name.  The format style is first tested for the  given
              tag  and  then  for  the descriptions tag if no value was found,
              while the remainder are only tested for the  tag  given  as  the
              first argument.  The function also calls _setup which tests some
              more styles.

              The string returned by the format style (if any) will  be  modi-
              fied so that the sequence `%d' is replaced by the descr given as
              the third argument without any leading or trailing white  space.
              If,  after  removing  the  white  space,  the descr is the empty
              string, the format style will not be used and  the  options  put
              into the name array will not contain an explanation string to be
              displayed above the matches.

              If _description is called with more than  three  arguments,  the
              additional specs should be of the form `char:str'.  These supply
              escape sequence replacements for the format style: every appear-
              ance of `%char' will be replaced by string.

              If  the  -x  option  is given, the description will be passed to
              compadd using the -x option instead of  the  default  -X.   This
              means  that  the description will be displayed even if there are
              no corresponding matches.

              The options placed  in  the  array  name  take  account  of  the
              group-name  style,  so  matches  are  placed in a separate group
              where necessary.  The group normally has its elements sorted (by
              passing  the  option  -J  to compadd), but if an option starting
              with `-V', `-J', `-1', or `-2' is passed to  _description,  that
              option  will be included in the array.  Hence it is possible for
              the completion group to be unsorted by giving the  option  `-V',
              `-1V', or `-2V'.

              In most cases, the function will be used like this:

                     local expl
                     _description files expl file
                     compadd "$expl[@]" - "$files[@]"

              Note  the use of the parameter expl, the hyphen, and the list of
              matches.  Almost all calls to compadd within the completion sys-
              tem  use  a  similar  format;  this  ensures that user-specified
              styles are correctly passed down to the builtins which implement
              the internals of completion.

       _dir_list [ -s sep ] [ -S ]
              Complete a list of directory names separated by colons (the same
              format as $PATH).

              -s sep Use sep as separator between items.  sep  defaults  to  a
                     colon (`:').

              -S     Add  sep instead of slash (`/') as an autoremoveable suf-
                     fix.

       _dispatch context string ...
              This sets the current context to context and looks  for  comple-
              tion  functions  to  handle  this context by hunting through the
              list of command names or special contexts  (as  described  above
              for compdef) given as strings.  The first completion function to
              be defined for one of the contexts in the list is used to gener-
              ate  matches.   Typically, the last string is -default- to cause
              the function for default completion to be used as a fallback.

              The function sets the parameter $service  to  the  string  being
              tried,  and  sets  the context/command field (the fourth) of the
              $curcontext parameter to the context given as  the  first  argu-
              ment.

       _email_addresses [ -c ] [ -n plugin ]
              Complete email addresses.  Addresses are provided by plugins.

              -c     Complete  bare  localhost@domain.tld addresses, without a
                     name part or a  comment.   Without  this  option,  RFC822
                     `Firstname Lastname <address>' strings are completed.

              -n plugin
                     Complete aliases from plugin.

              The following plugins are available by default: _email-ldap (see
              the filter style), _email-local  (completes  user@hostname  Unix
              addresses),  _email-mail  (completes  aliases  from  ~/.mailrc),
              _email-mush, _email-mutt, and _email-pine.

              Addresses from the _email-foo plugin are  added  under  the  tag
              `email-foo'.

              Writing plugins

              Plugins  are  written  as separate functions with names starting
              with `_email-'.  They are invoked with the -c option and compadd
              options.   They should either do their own completion or set the
              $reply array to a list of `alias:address'  elements  and  return
              300.  New plugins will be picked up and run automatically.

       _files The  function _files calls _path_files with all the arguments it
              was passed except for -g and -/.  The use of these  two  options
              depends on the setting of the  file-patterns style.

              This  function  accepts  the  full  set  of  options  allowed by
              _path_files, described below.

       _gnu_generic
              This function is a simple wrapper around the _arguments function
              described  above.  It can be used to determine automatically the
              long options understood by commands that  produce  a  list  when
              passed  the  option  `--help'.   It  is intended to be used as a
              top-level completion function in its own right.  For example, to
              enable option completion for the commands foo and bar, use

                     compdef _gnu_generic foo bar

              after the call to compinit.

              The  completion system as supplied is conservative in its use of
              this function, since it is important  to  be  sure  the  command
              understands the option `--help'.

       _guard [ options ] pattern descr
              This function displays descr if pattern matches the string to be
              completed.  It is intended to be used  in  the  action  for  the
              specifications passed to _arguments and similar functions.

              The  return  status is zero if the message was displayed and the
              word to complete is not empty, and non-zero otherwise.

              The pattern may be preceded by any of the options understood  by
              compadd  that  are passed down from _description, namely -M, -J,
              -V, -1, -2, -n, -F  and  -X.   All  of  these  options  will  be
              ignored.   This  fits  in conveniently with the argument-passing
              conventions of actions for _arguments.

              As an example, consider a command  taking  the  options  -n  and
              -none,  where -n must be followed by a numeric value in the same
              word.  By using:

                     _arguments '-n-: :_guard "[0-9]#" "numeric value"' '-none'

              _arguments can be made to  both  display  the  message  `numeric
              value'  and  complete  options  after `-n<TAB>'.  If the `-n' is
              already followed by one or more digits (the  pattern  passed  to
              _guard)  only the message will be displayed; if the `-n' is fol-
              lowed by another character, only options are completed.

       _message [ -r12 ] [ -VJ group ] descr
       _message -e [ tag ] descr
              The descr is used in the same way as the third argument  to  the
              _description  function,  except  that  the resulting string will
              always be shown whether or not matches were generated.  This  is
              useful  for displaying a help message in places where no comple-
              tions can be generated.

              The format style is examined with the messages  tag  to  find  a
              message;  the usual tag, descriptions, is used only if the style
              is not set with the former.

              If the -r option is given, no style is used; the descr is  taken
              literally  as  the  string to display.  This is most useful when
              the descr comes from a pre-processed argument list which already
              contains an expanded description.

              The  -12VJ options and the group are passed to compadd and hence
              determine the group the message string is added to.

              The second -e form gives a description for completions with  the
              tag  tag  to be shown even if there are no matches for that tag.
              This form is called by _arguments in the event that there is  no
              action  for an option specification.  The tag can be omitted and
              if so the tag is taken from the parameter $curtag; this is main-
              tained by the completion system and so is usually correct.  Note
              that if there are no  matches  at  the  time  this  function  is
              called, compstate[insert] is cleared, so additional matches gen-
              erated later are not inserted on the command line.

       _multi_parts [ -i ] sep array
              The argument sep is a separator character.   The  array  may  be
              either  the name of an array parameter or a literal array in the
              form `(foo bar)', a parenthesised list  of  words  separated  by
              whitespace.   The  possible completions are the strings from the
              array.  However, each chunk delimited by sep will  be  completed
              separately.  For example, the _tar function uses `_multi_parts /
              patharray' to complete partial file paths from the  given  array
              of complete file paths.

              The  -i option causes _multi_parts to insert a unique match even
              if that requires multiple separators to be  inserted.   This  is
              not  usually  the expected behaviour with filenames, but certain
              other types of completion, for example those with a fixed set of
              possibilities, may be more suited to this form.

              Like  other  utility  functions, this function accepts the `-V',
              `-J', `-1', `-2', `-n', `-f',  `-X',  `-M',  `-P',  `-S',  `-r',
              `-R', and `-q' options and passes them to the compadd builtin.

       _next_label [ -x ] [ -12VJ ] tag name descr [ option ... ]
              This  function  is used to implement the loop over different tag
              labels for a particular tag as described above for the tag-order
              style.   On each call it checks to see if there are any more tag
              labels; if there is it returns status zero, otherwise  non-zero.
              As  this  function  requires  a  current  tag to be set, it must
              always follow a call to _tags or _requested.

              The -x12VJ options and the first three arguments are  passed  to
              the  _description  function.   Where appropriate the tag will be
              replaced by a tag label in this call.  Any description given  in
              the  tag-order  style  is  preferred  to  the  descr  passed  to
              _next_label.

              The options given after the descr are set in the parameter given
              by name, and hence are to be passed to compadd or whatever func-
              tion is called to add the matches.

              Here is a typical use of this function for  the  tag  foo.   The
              call to _requested determines if tag foo is required at all; the
              loop over _next_label handles any labels defined for the tag  in
              the tag-order style.

                     local expl ret=1
                     ...
                     if _requested foo; then
                       ...
                       while _next_label foo expl '...'; do
                         compadd "$expl[@]" ... && ret=0
                       done
                       ...
                     fi
                     return ret

       _normal
              This  is  the standard function called to handle completion out-
              side any special -context-.  It is called both to  complete  the
              command  word and also the arguments for a command.  In the sec-
              ond case, _normal looks for a special completion for  that  com-
              mand,  and  if  there  is  none  it  uses the completion for the
              -default- context.

              A second use is to reexamine the command line specified  by  the
              $words  array  and  the $CURRENT parameter after those have been
              modified.  For example, the  function  _precommand,  which  com-
              pletes  after  pre-command specifiers such as nohup, removes the
              first word from the words array, decrements the CURRENT  parame-
              ter,  then  calls  _normal again.  The effect is that `nohup cmd
              ...' is treated in the same way as `cmd ...'.

              If the command name matches one of the patterns given by one  of
              the  options  -p  or -P to compdef, the corresponding completion
              function is called and then the parameter _compskip is  checked.
              If  it  is set completion is terminated at that point even if no
              matches have been found.  This is the  same  effect  as  in  the
              -first- context.

       _options
              This  can  be  used  to complete the names of shell options.  It
              provides a matcher specification that ignores  a  leading  `no',
              ignores underscores and allows upper-case letters to match their
              lower-case  counterparts   (for   example,   `glob',   `noglob',
              `NO_GLOB'  are  all completed).  Any arguments are propagated to
              the compadd builtin.

       _options_set and _options_unset
              These functions complete only set or  unset  options,  with  the
              same matching specification used in the _options function.

              Note  that  you  need to uncomment a few lines in the _main_com-
              plete function for these functions to work properly.  The  lines
              in  question  are  used  to  store the option settings in effect
              before the completion widget locally sets the options it  needs.
              Hence  these  functions are not generally used by the completion
              system.

       _parameters
              This is used to complete the names of shell parameters.

              The option `-g pattern'  limits  the  completion  to  parameters
              whose type matches the pattern.  The type of a parameter is that
              shown by `print ${(t)param}', hence judicious use of `*' in pat-
              tern is probably necessary.

              All other arguments are passed to the compadd builtin.

       _path_files
              This  function  is used throughout the completion system to com-
              plete filenames.  It allows completion of  partial  paths.   For
              example,   the   string   `/u/i/s/sig'   may   be  completed  to
              `/usr/include/sys/signal.h'.

              The options accepted by both _path_files and _files are:

              -f     Complete all filenames.  This is the default.

              -/     Specifies that only directories should be completed.

              -g pattern
                     Specifies that only files matching the pattern should  be
                     completed.

              -W paths
                     Specifies  path  prefixes that are to be prepended to the
                     string from the command line to  generate  the  filenames
                     but  that should not be inserted as completions nor shown
                     in completion listings.  Here, paths may be the  name  of
                     an  array  parameter, a literal list of paths enclosed in
                     parentheses or an absolute pathname.

              -F ignored-files
                     This behaves as for the corresponding option to the  com-
                     padd  builtin.   It gives direct control over which file-
                     names should be ignored.  If the option is  not  present,
                     the ignored-patterns style is used.

              Both  _path_files  and  _files also accept the following options
              which are passed to compadd: `-J', `-V', `-1', `-2', `-n', `-X',
              `-M', `-P', `-S', `-q', `-r', and `-R'.

              Finally,  the  _path_files  function   uses  the  styles expand,
              ambiguous, special-dirs, list-suffixes and  file-sort  described
              above.


       _pick_variant [ -b builtin-label ] [ -c command ] [ -r name ]
                     label=pattern ... label [ arg ... ]
              This  function is used to resolve situations where a single com-
              mand name requires  more  than  one  type  of  handling,  either
              because  it has more than one variant or because there is a name
              clash between two different commands.

              The command to run is taken from the first element of the  array
              words  unless this is overridden by the option -c.  This command
              is run and its output is compared with  a  series  of  patterns.
              Arguments  to  be  passed to the command can be specified at the
              end after all the other arguments.  The patterns to try in order
              are given by the arguments label=pattern; if the output of `com-
              mand arg ...' contains pattern, then label is  selected  as  the
              label  for  the command variant.  If none of the patterns match,
              the final command label is selected and status 1 is returned.

              If the `-b builtin-label' is given, the command is tested to see
              if  it  is  provided as a shell builtin, possibly autoloaded; if
              so, the label builtin-label is selected as  the  label  for  the
              variant.

              If  the  `-r  name'  is given, the label picked is stored in the
              parameter named name.

              The results are also  cached  in  the  _cmd_variant  associative
              array indexed by the name of the command run.

       _regex_arguments name spec ...
              This function generates a completion function name which matches
              the specifications  specs,  a  set  of  regular  expressions  as
              described  below.   After running _regex_arguments, the function
              name should be called as a normal completion function.  The pat-
              tern  to  be matched is given by the contents of the words array
              up to the current cursor  position  joined  together  with  null
              characters; no quotation is applied.

              The  arguments  are grouped as sets of alternatives separated by
              `|', which are tried one after  the  other  until  one  matches.
              Each  alternative consists of a one or more specifications which
              are tried  left  to  right,  with  each  pattern  matched  being
              stripped  in  turn from the command line being tested, until all
              of the group succeeds or until one fails; in  the  latter  case,
              the  next  alternative is tried.  This structure can be repeated
              to arbitrary depth by using parentheses; matching proceeds  from
              inside to outside.

              A  special  procedure  is  applied  if  no test succeeds but the
              remaining command line string contains no null character (imply-
              ing  the  remaining word is the one for which completions are to
              be generated).  The  completion  target  is  restricted  to  the
              remaining  word  and  any actions for the corresponding patterns
              are executed.  In this case, nothing is stripped from  the  com-
              mand line string.  The order of evaluation of the actions can be
              determined by the tag-order style; the various formats supported
              by  _alternative  can  be used in action.  The descr is used for
              setting up the array parameter expl.

              Specification arguments take one of following  forms,  in  which
              metacharacters such as `(', `)', `#' and `|' should be quoted.

              /pattern/ [%lookahead%] [-guard] [:tag:descr:action]
                     This is a single primitive component.  The function tests
                     whether  the  combined  pattern  `(#b)((#B)pattern)looka-
                     head*'  matches  the command line string.  If so, `guard'
                     is evaluated and its return status is examined to  deter-
                     mine  if the test has succeeded.  The pattern string `[]'
                     is guaranteed never  to  match.   The  lookahead  is  not
                     stripped from the command line before the next pattern is
                     examined.

                     The argument starting with : is used in the  same  manner
                     as an argument to _alternative.

                     A  component is used as follows: pattern is tested to see
                     if the component already exists on the command line.   If
                     it  does,  any  following  specifications are examined to
                     find something to complete.  If a  component  is  reached
                     but  no  such pattern exists yet on the command line, the
                     string containing the action is used to generate  matches
                     to insert at that point.

              /pattern/+ [%lookahead%] [-guard] [:tag:descr:action]
                     This  is  similar to `/pattern/ ...' but the left part of
                     the command line string (i.e. the part already matched by
                     previous patterns) is also considered part of the comple-
                     tion target.

              /pattern/- [%lookahead%] [-guard] [:tag:descr:action]
                     This is similar to `/pattern/ ...' but the actions of the
                     current  and previously matched patterns are ignored even
                     if the following `pattern' matches the empty string.

              ( spec )
                     Parentheses may be used to groups specs; note each paren-
                     thesis is a single argument to _regex_arguments.

              spec # This allows any number of repetitions of spec.

              spec spec
                     The  two  specs  are to be matched one after the other as
                     described above.

              spec | spec
                     Either of the two specs can be matched.

              The function _regex_words can be used as a  helper  function  to
              generate  matches  for  a set of alternative words possibly with
              their own arguments as a command line argument.

              Examples:

                     _regex_arguments _tst /$'[^\0]#\0'/ \
                         /$'[^\0]#\0'/ :'compadd aaa'

              This generates a function _tst that completes aaa  as  its  only
              argument.   The  tag  and  description  for the action have been
              omitted for brevity (this works but is not recommended in normal
              use).   The  first  component matches the command word, which is
              arbitrary; the second matches  any argument.  As the argument is
              also  arbitrary, any following component would not depend on aaa
              being present.

                     _regex_arguments _tst /$'[^\0]#\0'/ \
                         /$'aaa\0'/ :'compadd aaa'

              This is a more typical use; it is  similar,  but  any  following
              patterns  would only match if aaa was present as the first argu-
              ment.

                     _regex_arguments _tst /$'[^\0]#\0'/ \( \
                         /$'aaa\0'/ :'compadd aaa' \
                         /$'bbb\0'/ :'compadd bbb' \) \#

              In this example, an indefinite number of command  arguments  may
              be completed.  Odd arguments are completed as aaa and even argu-
              ments as bbb.  Completion fails unless the set of  aaa  and  bbb
              arguments before the current one is matched correctly.

                     _regex_arguments _tst /$'[^\0]#\0'/ \
                         \( /$'aaa\0'/ :'compadd aaa' \| \
                         /$'bbb\0'/ :'compadd bbb' \) \#

              This  is similar, but either aaa or bbb may be completed for any
              argument.  In this case _regex_words could be used to generate a
              suitable expression for the arguments.

       _regex_words tag description spec ...
              This  function  can  be  used  to  generate  arguments  for  the
              _regex_arguments command which may  be  inserted  at  any  point
              where  a set of rules is expected.  The tag and description give
              a standard tag and description pertaining to  the  current  con-
              text.   Each spec contains two or three arguments separated by a
              colon: note that there is no leading colon in this case.

              Each spec gives one of a set of words that may be  completed  at
              this point, together with arguments.  It is thus roughly equiva-
              lent to the _arguments function when used in normal  (non-regex)
              completion.

              The  part  of  the spec before the first colon is the word to be
              completed.  This may contain a *; the entire  word,  before  and
              after  the  *  is  completed,  but only the text before the * is
              required for the context to be matched, so  that  further  argu-
              ments may be completed after the abbreviated form.

              The second part of spec is a description for the word being com-
              pleted.

              The optional third part of the spec describes how words  follow-
              ing  the one being completed are themselves to be completed.  It
              will be evaluated in order to avoid problems with quoting.  This
              means  that  typically  it contains a reference to an array con-
              taining previously generated regex arguments.

              The option -t term specifies a terminator for the  word  instead
              of the usual space.  This is handled as an auto-removable suffix
              in the manner of the option -s sep to _values.

              The result of the processing by _regex_words is  placed  in  the
              array reply, which should be made local to the calling function.
              If the set of words and arguments may be matched repeatedly, a #
              should be appended to the generated array at that point.

              For example:

                     local -a reply
                     _regex_words mydb-commands 'mydb commands' \
                       'add:add an entry to mydb:$mydb_add_cmds' \
                       'show:show entries in mydb'
                     _regex_arguments _mydb "$reply[@]"
                     _mydb "$@"

              This  shows a completion function for a command mydb which takes
              two command arguments, add and show.  show takes  no  arguments,
              while  the  arguments  for  add have already been prepared in an
              array mydb_add_cmds,  quite  possibly  by  a  previous  call  to
              _regex_words.

       _requested [ -x ] [ -12VJ ] tag [ name descr [ command [ arg ... ] ]
              This  function  is called to decide whether a tag already regis-
              tered by a call to _tags (see below) has been requested  by  the
              user  and  hence  completion  should  be  performed  for it.  It
              returns status zero if the tag is requested and non-zero  other-
              wise.   The  function  is  typically used as part of a loop over
              different tags as follows:

                     _tags foo bar baz
                     while _tags; do
                       if _requested foo; then
                         ... # perform completion for foo
                       fi
                       ... # test the tags bar and baz in the same way
                       ... # exit loop if matches were generated
                     done

              Note that the test for whether matches  were  generated  is  not
              performed  until the end of the _tags loop.  This is so that the
              user can set the tag-order style to specify a set of tags to  be
              completed at the same time.

              If  name  and descr are given, _requested calls the _description
              function with these arguments together with the  options  passed
              to _requested.

              If  command  is  given,  the _all_labels function will be called
              immediately with the same arguments.  In simple cases this makes
              it  possible to perform the test for the tag and the matching in
              one go.  For example:

                     local expl ret=1
                     _tags foo bar baz
                     while _tags; do
                       _requested foo expl 'description' \
                           compadd foobar foobaz && ret=0
                       ...
                       (( ret )) || break
                     done

              If the command is not compadd, it must nevertheless be  prepared
              to handle the same options.

       _retrieve_cache cache_identifier
              This  function  retrieves  completion  information from the file
              given by cache_identifier, stored in a  directory  specified  by
              the  cache-path  style  which  defaults  to  ~/.zcompcache.  The
              return status is zero if retrieval was successful.  It will only
              attempt retrieval if the use-cache style is set, so you can call
              this function without worrying about whether the user wanted  to
              use the caching layer.

              See _store_cache below for more details.

       _sep_parts
              This  function  is  passed  alternating arrays and separators as
              arguments.  The arrays specify completions for parts of  strings
              to  be separated by the separators.  The arrays may be the names
              of array parameters or a quoted list of  words  in  parentheses.
              For   example,  with  the  array  `hosts=(ftp  news)'  the  call
              `_sep_parts '(foo bar)' @ hosts' will complete the  string   `f'
              to `foo' and the string `b@n' to `bar@news'.

              This  function  accepts  the  compadd  options `-V', `-J', `-1',
              `-2', `-n', `-X', `-M', `-P', `-S', `-r',  `-R',  and  `-q'  and
              passes them on to the compadd builtin used to add the matches.

       _sequence [ -s sep ] [ -n max ] [ -d ] function [ - ] ...
              This  function  is  a  wrapper to other functions for completing
              items in a separated list. The same function is used to complete
              each  item  in  the list. The separator is specified with the -s
              option. If -s is omitted it will use `,'. Duplicate  values  are
              not matched unless -d is specified. If there is a fixed or maxi-
              mum number of items in the list, this can be specified with  the
              -n option.

              Common compadd options are passed on to the function. It is pos-
              sible to use compadd directly with _sequence, though _values may
              be more appropriate in this situation.

       _setup tag [ group ]
              This function sets up the special parameters used by the comple-
              tion system appropriately for the tag given as the  first  argu-
              ment.     It   uses   the   styles   list-colors,   list-packed,
              list-rows-first, last-prompt, accept-exact, menu and force-list.

              The optional group supplies the name of the group in  which  the
              matches  will be placed.  If it is not given, the tag is used as
              the group name.

              This function is  called  automatically  from  _description  and
              hence is not normally called explicitly.

       _store_cache cache_identifier param ...
              This function, together with _retrieve_cache and _cache_invalid,
              implements a caching layer which can be used in  any  completion
              function.   Data  obtained  by  costly  operations are stored in
              parameters; this function then dumps the values of those parame-
              ters  to  a  file.   The data can then be retrieved quickly from
              that file via _retrieve_cache, even in  different  instances  of
              the shell.

              The cache_identifier specifies the file which the data should be
              dumped to.  The file is stored in a directory specified  by  the
              cache-path style which defaults to ~/.zcompcache.  The remaining
              params arguments are the parameters to dump to the file.

              The return status is zero if storage was successful.  The  func-
              tion will only attempt storage if the use-cache style is set, so
              you can call this function without worrying  about  whether  the
              user wanted to use the caching layer.

              The  completion  function may avoid calling _retrieve_cache when
              it already has the  completion  data  available  as  parameters.
              However,  in  that  case  it should call _cache_invalid to check
              whether the data in the parameters and in the  cache  are  still
              valid.

              See  the  _perl_modules completion function for a simple example
              of the usage of the caching layer.

       _tags [ [ -C name ] tag ... ]
              If called with arguments, these are taken to  be  the  names  of
              tags  valid  for completions in the current context.  These tags
              are stored internally and sorted by using the tag-order style.

              Next, _tags is called repeatedly without arguments from the same
              completion  function.  This successively selects the first, sec-
              ond, etc. set of tags requested by the user.  The return  status
              is  zero  if  at least one of the tags is requested and non-zero
              otherwise.  To test if a particular tag  is  to  be  tried,  the
              _requested function should be called (see above).

              If  `-C  name' is given, name is temporarily stored in the argu-
              ment field (the fifth) of the context in the curcontext  parame-
              ter  during  the  call  to _tags; the field is restored on exit.
              This allows _tags to use a more specific context without  having
              to change and reset the curcontext parameter (which has the same
              effect).

       _tilde_files
              Like _files, but resolve leading tildes according to  the  rules
              of  filename expansion, so the suggested completions don't start
              with a `~' even if the filename on the command-line does.

       _values [ -O name ] [ -s sep ] [ -S sep ] [ -wC ] desc spec ...
              This is used to complete arbitrary keywords (values)  and  their
              arguments, or lists of such combinations.

              If  the  first argument is the option `-O name', it will be used
              in the same way as by the _arguments function.  In other  words,
              the  elements  of  the name array will be passed to compadd when
              executing an action.

              If the first argument (or the first argument after `-O name') is
              `-s',  the next argument is used as the character that separates
              multiple values.  This character is  automatically  added  after
              each  value in an auto-removable fashion (see below); all values
              completed by `_values -s' appear in the same word on the command
              line, unlike completion using _arguments.  If this option is not
              present, only a single value will be completed per word.

              Normally, _values will only use the current  word  to  determine
              which  values  are already present on the command line and hence
              are not to be completed again.  If the -w option is given, other
              arguments are examined as well.

              The  first non-option argument is used as a string to print as a
              description before listing the values.

              All other arguments describe the possible values and their argu-
              ments  in the same format used for the description of options by
              the _arguments function (see above).  The only  differences  are
              that  no minus or plus sign is required at the beginning, values
              can have only one argument, and the forms  of  action  beginning
              with an equal sign are not supported.

              The  character  separating  a value from its argument can be set
              using the option -S (like -s, followed by the character  to  use
              as  the  separator in the next argument).  By default the equals
              sign will be used as the separator between values and arguments.

              Example:

                     _values -s , 'description' \
                             '*foo[bar]' \
                             '(two)*one[number]:first count:' \
                             'two[another number]::second count:(1 2 3)'

              This describes three possible values: `foo', `one',  and  `two'.
              The  first  is  described  as  `bar',  takes no argument and may
              appear more than once.  The second is described as `number', may
              appear   more  than  once,  and  takes  one  mandatory  argument
              described as `first count'; no action is specified, so  it  will
              not be completed.  The `(two)' at the beginning says that if the
              value `one' is on the line, the value `two' will  no  longer  be
              considered  a  possible  completion.   Finally,  the  last value
              (`two') is described as `another number' and takes  an  optional
              argument  described  as `second count' for which the completions
              (to appear after an `=') are `1', `2',  and  `3'.   The  _values
              function  will  complete lists of these values separated by com-
              mas.

              Like _arguments, this function temporarily adds another  context
              name  component to the arguments element (the fifth) of the cur-
              rent context while executing the action.  Here this name is just
              the name of the value for which the argument is completed.

              The  style verbose is used to decide if the descriptions for the
              values (but not those for the arguments) should be printed.

              The associative array val_args is  used  to  report  values  and
              their  arguments;  this works similarly to the opt_args associa-
              tive array used by _arguments.  Hence the function calling _val-
              ues  should  declare  the  local  parameters state, state_descr,
              line, context and val_args:

                     local context state state_descr line
                     typeset -A val_args

              when using an action of the form `->string'.  With this function
              the context parameter will be set to the name of the value whose
              argument is to be completed.  Note that for _values,  the  state
              and  state_descr  are scalars rather than arrays.  Only a single
              matching state is returned.

              Note also that _values normally adds the character used  as  the
              separator between values as an auto-removable suffix (similar to
              a `/' after a directory).  However, this is not possible  for  a
              `->string'  action as the matches for the argument are generated
              by the calling function.  To get the usual behaviour, the  call-
              ing  function can add the separator x as a suffix by passing the
              options `-qS x' either directly or indirectly to compadd.

              The option -C is treated in the same way as it is by _arguments.
              In  that  case  the  parameter  curcontext  should be made local
              instead of context (as described above).

       _wanted [ -x ] [ -C name ]  [ -12VJ ] tag name descr command [ arg ...]
              In many contexts, completion can only  generate  one  particular
              set of matches, usually corresponding to a single tag.  However,
              it is still  necessary  to  decide  whether  the  user  requires
              matches of this type.  This function is useful in such a case.

              The  arguments  to  _wanted are the same as those to _requested,
              i.e. arguments to be passed to _description.  However,  in  this
              case  the  command is not optional;  all the processing of tags,
              including the loop over both tags and tag labels and the genera-
              tion of matches, is carried out automatically by _wanted.

              Hence  to offer only one tag and immediately add the correspond-
              ing matches with the given description:

                     local expl
                     _wanted tag expl 'description' \
                         compadd matches...

              Note that, as for _requested, the command must be able to accept
              options to be passed down to compadd.

              Like  _tags  this function supports the -C option to give a dif-
              ferent name for the argument context field.  The -x  option  has
              the same meaning as for _description.

       _widgets [ -g pattern ]
              This  function  completes  names of zle widgets (see the section
              `Widgets' in zshzle(1)).  The pattern, if  present,  is  matched
              against  values of the $widgets special parameter, documented in
              the section `The zsh/zleparameter Module' in zshmodules(1).

COMPLETION SYSTEM VARIABLES
       There are some standard variables, initialised  by  the  _main_complete
       function and then used from other functions.

       The standard variables are:

       _comp_caller_options
              The  completion  system  uses setopt to set a number of options.
              This allows functions to be written without concern for compati-
              bility with every possible combination of user options. However,
              sometimes completion needs to know what the user's option  pref-
              erences  are.  These are saved in the _comp_caller_options asso-
              ciative array. Option names, spelled in lowercase without under-
              scores,  are  mapped  to  one  or  other of the strings `on' and
              `off'.

              _comp_priv_prefix
                     Completion  functions  such  as   _sudo   can   set   the
                     _comp_priv_prefix array to a command prefix that may then
                     be used by _call_program to  match  the  privileges  when
                     calling programs to generate matches.

              Two  more  features  are offered by the _main_complete function.
              The arrays compprefuncs and comppostfuncs may contain  names  of
              functions that are to be called immediately before or after com-
              pletion has been tried.  A function will  only  be  called  once
              unless it explicitly reinserts itself into the array.

COMPLETION DIRECTORIES
       In  the  source distribution, the files are contained in various subdi-
       rectories of the Completion directory.  They may have been installed in
       the same structure, or into one single function directory.  The follow-
       ing is a description of the  files  found  in  the  original  directory
       structure.   If  you  wish to alter an installed file, you will need to
       copy it to some directory which appears earlier in your fpath than  the
       standard directory where it appears.

       Base   The  core functions and special completion widgets automatically
              bound to keys.  You will certainly need most  of  these,  though
              will  probably  not need to alter them.  Many of these are docu-
              mented above.

       Zsh    Functions for completing arguments of shell builtin commands and
              utility  functions  for  this.   Some  of these are also used by
              functions from the Unix directory.

       Unix   Functions for completing  arguments  of  external  commands  and
              suites  of  commands.   They may need modifying for your system,
              although in many cases some attempt is made to decide which ver-
              sion  of  a command is present.  For example, completion for the
              mount command tries to determine the system it  is  running  on,
              while  completion for many other utilities try to decide whether
              the GNU version of the command is in use, and hence whether  the
              --help option is supported.

       X, AIX, BSD, ...
              Completion  and  utility function for commands available only on
              some systems.  These are not arranged  hierarchically,  so,  for
              example, both the Linux and Debian directories, as well as the X
              directory, may be useful on your system.



zsh 5.6.2                     September 14, 2018                 ZSHCOMPSYS(1)