ruby
(1)
Name
ruby - oriented scripting language
Synopsis
ruby [--copyright] [--version] [-SUacdlnpswvy] [-0[octal]]
[-C directory] [-E external[]]:internal [-F pattern] [-I
directory] [-K c] [-T[level]] [-W[level]] [-e command]
[-i[extension]] [-r library] [-x[directory]] [-Bro
enable|disable Brc-FEATURE] [--dump=target] [--verbose] [--]
[program_file] [argument ...]
Description
UNIX RUBY(1)
NAME
ruby - Interpreted object-oriented scripting language
SYNOPSIS
ruby [--copyright] [--version] [-SUacdlnpswvy] [-0[octal]]
[-C directory] [-E external[]]:internal [-F pattern] [-I
directory] [-K c] [-T[level]] [-W[level]] [-e command]
[-i[extension]] [-r library] [-x[directory]] [-Bro
enable|disable Brc-FEATURE] [--dump=target] [--verbose] [--]
[program_file] [argument ...]
DESCRIPTION
Ruby is an interpreted scripting language for quick and easy
object-oriented programming. It has many features to
process text files and to do system management tasks (as in
Perl). It is simple, straight-forward, and extensible.
If you want a language for easy object-oriented programming,
or you don't like the Perl ugliness, or you do like the con-
cept of LISP, but don't like too many parentheses, Ruby
might be your language of choice.
FEATURES
Ruby's features are as follows:
Interpretive
Ruby is an interpreted language, so you don't have to
recompile programs written in Ruby to execute them.
Variables have no type (dynamic typing)
Variables in Ruby can contain data of any type. You
don't have to worry about variable typing. Conse-
quently, it has a weaker compile time check.
No declaration needed
You can use variables in your Ruby programs without any
declarations. Variable names denote their scope -
global, class, instance, or local.
Simple syntax
Ruby has a simple syntax influenced slightly from Eif-
fel.
No user-level memory management
Ruby has automatic memory management. Objects no
longer referenced from anywhere are automatically col-
lected by the garbage collector built into the inter-
preter.
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Everything is an object
Ruby is a purely object-oriented language, and was so
since its creation. Even such basic data as integers
are seen as objects.
Class, inheritance, and methods
Being an object-oriented language, Ruby naturally has
basic features like classes, inheritance, and methods.
Singleton methods
Ruby has the ability to define methods for certain
objects. For example, you can define a press-button
action for certain widget by defining a singleton
method for the button. Or, you can make up your own
prototype based object system using singleton methods,
if you want to.
Mix-in by modules
Ruby intentionally does not have the multiple inheri-
tance as it is a source of confusion. Instead, Ruby
has the ability to share implementations across the
inheritance tree. This is often called a `Mix-in'.
Iterators
Ruby has iterators for loop abstraction.
Closures
In Ruby, you can objectify the procedure.
Text processing and regular expressions
Ruby has a bunch of text processing features like in
Perl.
M17N, character set independent
Ruby supports multilingualized programming. Easy to
process texts written in many different natural lan-
guages and encoded in many different character encod-
ings, without dependence on Unicode.
Bignums
With built-in bignums, you can for example calculate
factorial(400).
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Reflection and domain specific languages
Class is also an instance of the Class class. Defini-
tion of classes and methods is an expression just as
1+1 is. So your programs can even write and modify pro-
grams. Thus you can write your application in your own
programming language on top of Ruby.
Exception handling
As in Java(tm).
Direct access to the OS
Ruby can use most UNIX system calls, often used in sys-
tem programming.
Dynamic loading
On most UNIX systems, you can load object files into
the Ruby interpreter on-the-fly.
Rich libraries
Libraries called "builtin libraries" and "standard
libraries" are bundled with Ruby. And you can obtain
more libraries via the package management system called
`RubyGems'.
Moreover there are thousands of Ruby projects in Ruby-
forge ( "http://www.rubyforge.org") and RAA (
"http://raa.ruby-lang.org").
OPTIONS
Ruby interpreter accepts following command-line options
(switches). They are quite similar to those of perl(1).
--copyright
Prints the copyright notice.
--version
Prints the version of Ruby interpreter.
-0[octal]
(The digit ``zero''.) Specifies the input record sepa-
rator ("$/") as an octal number. If no digit is given,
the null character is taken as the separator. Other
switches may follow the digits. -00 turns Ruby into
paragraph mode. -0777 makes Ruby read whole file at
once as a single string since there is no legal
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character with that value.
-C directory
-X directory
Causes Ruby to switch to the directory.
-E external[]:internal
--encoding external[]:internal
Specifies the default value(s) for external encodings
and internal encoding. Values should be separated with
colon (:).
You can omit the one for internal encodings, then the
value ("Encoding.default_internal") will be nil.
-F pattern
Specifies input field separator ("$;").
-I directory
Used to tell Ruby where to load the library scripts.
Directory path will be added to the load-path variable
("$:").
-K kcode
Specifies KANJI (Japanese) encoding. The default value
for script encodings ("__ENCODING__") and external
encodings ("Encoding.default_external") will be the
specified one. kcode can be one of
e EUC-JP
s Windows-31J (CP932)
u UTF-8
n ASCII-8BIT (BINARY)
-S Makes Ruby use the PATH environment variable to search
for script, unless if its name begins with a slash.
This is used to emulate #! on machines that don't sup-
port it, in the following manner:
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#! /usr/ruby/1.9/bin/ruby
# This line makes the next one a comment in Ruby \
exec /usr/ruby/1.9/bin/ruby -S $0 $*
-T[level=1]
Turns on taint checks at the specified level (default
1).
-U Sets the default value for internal encodings ("Encod-
ing.default_internal") to UTF-8.
-W[level=2]
Turns on verbose mode at the specified level, without
printing version message at the beginning. The level
can be;
0 Verbose mode is "silence". It sets the "$VERBOSE" to
nil.
1 Verbose mode is "medium". It sets the "$VERBOSE" to
false.
2 (default)
Verbose mode is "verbose". It sets the "$VERBOSE" to
true. -W 2 is same as -w
-a Turns on auto-split mode when used with -n or -p. In
auto-split mode, Ruby executes
$F = $_.split
at beginning of each loop.
-c Causes Ruby to check the syntax of the script and exit
without executing. If there are no syntax errors, Ruby
will print ``Syntax OK'' to the standard output.
-d
--debug
Turns on debug mode. "$DEBUG" will be set to true.
-e command
Specifies script from command-line while telling Ruby
not to search the rest of the arguments for a script
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file name.
-h
--help
Prints a summary of the options.
-i extension
Specifies in-place-edit mode. The extension, if speci-
fied, is added to old file name to make a backup copy.
For example:
% echo matz > /tmp/junk
% cat /tmp/junk
matz
% ruby -p -i.bak -e '$_.upcase!' /tmp/junk
% cat /tmp/junk
MATZ
% cat /tmp/junk.bak
matz
-l (The lowercase letter ``ell''.) Enables automatic
line-ending processing, which means to firstly set "$\"
to the value of "$/", and secondly chops every line
read using chop!.
-n Causes Ruby to assume the following loop around your
script, which makes it iterate over file name arguments
somewhat like sed -n or awk.
while gets
...
end
-p Acts mostly same as -n switch, but print the value of
variable "$_" at the each end of the loop. For exam-
ple:
% echo matz | ruby -p -e '$_.tr! "a-z", "A-Z"'
MATZ
-r library
Causes Ruby to load the library using require. It is
useful when using -n or -p.
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-s Enables some switch parsing for switches after script
name but before any file name arguments (or before a
--). Any switches found there are removed from ARGV
and set the corresponding variable in the script. For
example:
#! /usr/ruby/1.9/bin/ruby -s
# prints "true" if invoked with `-xyz' switch.
print "true\n" if $xyz
On some systems "$0" does not always contain the full
pathname, so you need the -S switch to tell Ruby to
search for the script if necessary. To handle embedded
spaces or such. A better construct than "$*" would be
${1+"$@"}, but it does not work if the script is being
interpreted by csh(1).
-v Enables verbose mode. Ruby will print its version at
the beginning, and set the variable "$VERBOSE" to true.
Some methods print extra messages if this variable is
true. If this switch is given, and no other switches
are present, Ruby quits after printing its version.
-w Enables verbose mode without printing version message
at the beginning. It sets the "$VERBOSE" variable to
true.
-x[directory]
Tells Ruby that the script is embedded in a message.
Leading garbage will be discarded until the first that
starts with ``#!'' and contains the string, ``ruby''.
Any meaningful switches on that line will applied. The
end of script must be specified with either EOF, "^D"
("control-D"), "^Z" ("control-Z"), or the reserved word
__END__. If the directory name is specified, Ruby will
switch to that directory before executing script.
-y
--yydebug
DO NOT USE.
Turns on compiler debug mode. Ruby will print a bunch
of internal state messages during compiling scripts.
You don't have to specify this switch, unless you are
going to debug the Ruby interpreter.
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--disable-FEATURE
--enable-FEATURE
Disables (or enables) the specified FEATURE .
--disable-gems
--enable-gems
Disables (or enables) RubyGems libraries. By default,
Ruby will load the latest version of each installed
gem. The Gem constant is true if RubyGems is enabled,
false if otherwise.
--disable-rubyopt
--enable-rubyopt
Ignores (or considers) the RUBYOPT environment vari-
able. By default, Ruby considers the variable.
--disable-all
--enable-all
Disables (or enables) all features.
--dump=target
DO NOT USE.
Prints the specified target. target can be one of;
insns
disassembled instructions
You don't have to specify this switch, unless you are
going to debug the Ruby interpreter.
--verbose
Enables verbose mode without printing version message
at the beginning. It sets the "$VERBOSE" variable to
true. If this switch is given, and no other switches
are present, Ruby quits after printing its version.
ENVIRONMENT
RUBYLIB
A colon-separated list of directories that are added to
Ruby's library load path ("$:"). Directories from this
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environment variable are searched before the standard
load path is searched.
e.g.:
RUBYLIB="$HOME/lib/ruby:$HOME/lib/rubyext"
RUBYOPT
Additional Ruby options.
e.g.
RUBYOPT="-w -Ke"
Note that RUBYOPT can contain only
-d,-E,-I,-K,-r,-T,-U,-v,-w,-W, --debug, --disable-FEA-
TURE and --enable-FEATURE.
RUBYPATH
A colon-separated list of directories that Ruby
searches for Ruby programs when the -S flag is speci-
fied. This variable precedes the PATH environment
variable.
RUBYSHELL
The path to the system shell command. This environment
variable is enabled for only mswin32, mingw32, and OS/2
platforms. If this variable is not defined, Ruby
refers to COMSPEC.
PATH Ruby refers to the PATH environment variable on calling
Kernel#system.
RUBYLIB_PREFIX
This variable is obsolete.
And Ruby depends on some RubyGems related environment
variables unless RubyGems is disabled. See the help of
gem(1) as bellow.
% gem help
ATTRIBUTES
See attributes(5) for descriptions of the following
attributes:
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+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | runtime/ruby-19 |
+---------------+------------------+
|Stability | Uncommitted |
+---------------+------------------+
SEE ALSO
http://www.ruby-lang.org
The official web site.
http://www.rubyforge.org
hosting many open source ruby projects.
http://raa.ruby-lang.org
Ruby Application Archive.
REPORTING BUGS
Security vulnerabilities should be reported via an email to
<security@ruby-lang.org> Reported problems will be published
after they've been fixed.
And you can report other bugs and feature requests via the
Ruby Issue Tracking System (http://redmine.ruby-lang.org).
Do not report security vulnerabilities via the system
because it publishes the vulnerabilities immediately.
AUTHORS
Ruby is designed and implemented by Yukihiro Matsumoto
<matz@netlab.jp>.
See <http://redmine.ruby-lang.org/wiki/ruby/Contributors>
for contributors to Ruby.
FILES
The following files specify the installation locations for
Ruby:
/usr/ruby/1.9/lib/MACH64/ruby/gems/1.9.1
Contains the Rubygems repository. Configure the
GEM_HOME environment variable to point to
/usr/ruby/1.9/lib/MACH64/ruby/gems/1.9.1 as the instal-
lation of Rubygems repository.
~/.gem/ruby/1.9.1
Per user location for gems, when installing with the
gem install option --user-install (gem install --user-
install ... ). This path is automatically added to
GEM_PATH.
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~/.gem/ruby/1.9.1/bin
Per user location for gem executables.
/usr/ruby/1.9/bin
Contains the Ruby executable as well as other util-
ity programs, and Rubygems programs. These programs are
linked from /usr/bin. For example:
/usr/ruby/1.9/bin/ruby is linked from /usr/bin/ruby19,
and may be linked from /usr/bin/ruby if the package
mediator "ruby" is version "1.9" (see pkg(1)). Also
contains executables for any installed gems that have
them (i.e.: thin, rails, etc).
NOTES
This software was built from source available at
https://java.net/projects/solaris-userland. The original
community source was downloaded from http://ftp.ruby-
lang.org/pub/ruby/1.9/ruby-1.9.3-p484.tar.gz
Further information about this software can be found on the
open source community website at http://www.ruby-lang.org/.
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