oracular (3) CPAN::Requirements::Dynamic.3pm.gz

NAME

       CPAN::Requirements::Dynamic - Dynamic prerequisites in meta files

VERSION

       version 0.001

SYNOPSIS

        my $result = $dynamic->evaluate({
          expressions => [
            {
              condition => [ 'has_perl' => 'v5.20.0' ],
              prereqs => { Bar => "1.3" },
            },
            {
              condition => [ is_os => 'linux' ],
              prereqs => { Baz => "1.4" },
            },
            {
              condition => [ config_defined => 'usethreads' ],
              prereqs => { Quz => "1.5" },
            },
            {
              condition => [ has_module => 'CPAN::Meta', '2' ],
              prereqs => { Wuz => "1.6" },
            },
            {
              condition => [ and =>
                [ config_defined => 'usethreads' ],
                [ is_os => 'openbsd' ],
              ],
              prereqs => { Euz => "1.7" },
            },
            {
              condition => [ not => is_os_type => 'Unix'],
              error => 'OS unsupported',
            },
          ],
        });

DESCRIPTION

       This module implements a format for describing dynamic prerequisites of a distribution.

METHODS

   new(%options)
       This constructor takes two (optional but recommended) named arguments

       •   config

           This is an ExtUtils::Config (compatible) object for reading configuration.

       •   pureperl_only

           This should be the value of the "pureperl-only" flag.

   evaluate(%options)
       This takes a hash with two named arguments: "version" and "expressions". The former is the version of the
       format, it currently defaults to 1. The latter is a list of hashes that can contain the following keys:

       •   condition

           The condition of the dynamic requirement. This is an array with a name as first values and zero or
           more arguments following it. The semantics are described below under "Conditions"

       •   prereqs

           The prereqs is a hash with modules for keys and the required version as values (e.g. "{ Foo =>
           '1.234' }").

       •   phase

           The phase of the requirements. This defaults to 'runtime'. Other valid values include 'build' and
           'test'.

       •   relation

           The relation of the requirements. This defaults to 'requires', but other valid values include
           'recommends', 'suggests' and 'conflicts'.

       •   error

           It will die with this error if set. The two messages "No support for OS" and "OS unsupported" have
           special meaning to CPAN Testers and are generally encouraged for situations that indicate not a
           failed build but an impossibility to build.

       "condition" and one of "prereqs" or "error" are mandatory.

   evaluate_file($filename)
       This takes a filename, that can be either a YAML file or a JSON file, and evaluates it.

   Conditions
       can_xs

       This returns true if a compiler appears to be available.

       can_run($command)

       Returns true if a $command can be run.

       config_defined($variable)

       This returns true if a specific configuration variable is defined.

       has_env($variable)

       This returns true if the environmental variable with the name in $variable is true.

       has_module($module, $version = 0)

       Returns true if a module is installed on the system. If a $version is given, it will also check if that
       version is provided. $version is interpreted exactly as in the CPAN::Meta spec.

       has_perl($version)

       Returns true if the perl version satisfies $version. $version is interpreted exactly as in the CPAN::Meta
       spec (e.g. 1.2 equals '>= 1.2').

       is_extended

       Returns true if extended testing is asked for.

       is_interactive

       Returns true if installed from a terminal that can answer prompts.

       is_os(@systems)

       Returns true if the OS name equals any of @systems.

       is_os_type($type)

       Returns true if the OS type equals $type. Typical values of $type are 'Unix' or 'Windows'.

       is_smoker

       Returns true when running on a smoker.

       has_env

       This returns true if the given environmental variable is true.

       prompt_default_no

       This will ask a yes/no question to the user, defaulting to no.

       prompt_default_yes

       This will ask a yes/no question to the user, defaulting to yes.

       want_pureperl

       This returns true if the user has indicated they want a pure-perl build.

       want_compiled

       This returns true if the user has explicitly indicated they do not want a pure-perl build.

       not

       This takes an expression and negates its value.

       or

       This takes list of arrayrefs, each containing a condition expression. If at least one of the conditions
       is true this will also return true.

       and

       This takes a list of arrayrefs, each containing a condition expression. If all of the conditions are true
       this will also return true.

AUTHOR

       Leon Timmermans <fawaka@gmail.com>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2023 by Leon Timmermans.

       This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5
       programming language system itself.