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Updated: Thursday, June 13, 2019
 
 

less (3)

Name

less - perl pragma to request less of something

Synopsis

use less 'CPU';

Description

Perl Programmers Reference Guide                                       less(3)



NAME
       less - perl pragma to request less of something

SYNOPSIS
           use less 'CPU';

DESCRIPTION
       This is a user-pragma. If you're very lucky some code you're using will
       know that you asked for less CPU usage or ram or fat or... we just
       can't know. Consult your documentation on everything you're currently
       using.

       For general suggestions, try requesting "CPU" or "memory".

           use less 'memory';
           use less 'CPU';
           use less 'fat';

       If you ask for nothing in particular, you'll be asking for "less
       'please'".

           use less 'please';

FOR MODULE AUTHORS
       less has been in the core as a "joke" module for ages now and it hasn't
       had any real way to communicating any information to anything. Thanks
       to Nicholas Clark we have user pragmas (see perlpragma) and now "less"
       can do something.

       You can probably expect your users to be able to guess that they can
       request less CPU or memory or just "less" overall.

       If the user didn't specify anything, it's interpreted as having used
       the "please" tag. It's up to you to make this useful.

         # equivalent
         use less;
         use less 'please';

   "BOOLEAN = less->of( FEATURE )"
       The class method "less->of( NAME )" returns a boolean to tell you
       whether your user requested less of something.

         if ( less->of( 'CPU' ) ) {
             ...
         }
         elsif ( less->of( 'memory' ) ) {

         }

   "FEATURES = less->of()"
       If you don't ask for any feature, you get the list of features that the
       user requested you to be nice to. This has the nice side effect that if
       you don't respect anything in particular then you can just ask for it
       and use it like a boolean.

         if ( less->of ) {
             ...
         }
         else {
             ...
         }

CAVEATS
       This probably does nothing.
       This works only on 5.10+
           At least it's backwards compatible in not doing much.



ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+-----------------------+
       |ATTRIBUTE TYPE |   ATTRIBUTE VALUE     |
       +---------------+-----------------------+
       |Availability   | runtime/perl-526      |
       +---------------+-----------------------+
       |Stability      | Pass-through volatile |
       +---------------+-----------------------+
NOTES
       This software was built from source available at
       https://github.com/oracle/solaris-userland.  The original community
       source was downloaded from
       http://www.cpan.org/src/5.0/perl-5.26.3.tar.bz2

       Further information about this software can be found on the open source
       community website at http://www.perl.org/.



perl v5.26.3                      2018-03-01                           less(3)