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NAME

Dist::Zilla::Plugin::DynamicPrereqs - Specify dynamic (user-side) prerequisites for your distribution

VERSION

version 0.009

SYNOPSIS

In your dist.ini:

    [DynamicPrereqs]
    -raw = $WriteMakefileArgs{PREREQ_PM}{'Role::Tiny'} = $FallbackPrereqs{'Role::Tiny'} = '1.003000'
    -raw = if eval { require Role::Tiny; 1 };

or:

    [DynamicPrereqs]
    -delimiter = |
    -raw = |$WriteMakefileArgs{TEST_REQUIRES}{'Devel::Cover'} = $FallbackPrereqs{'Devel::Cover'} = '0'
    -raw = |    if $ENV{EXTENDED_TESTING};

DESCRIPTION

This is a Dist::Zilla plugin that inserts code into your Makefile.PL to indicate dynamic (installer-side) prerequisites.

Code is inserted immediately after the declarations for %WriteMakefileArgs and %FallbackPrereqs, before they are conditionally modified (when an older ExtUtils::MakeMaker is installed). This gives you an opportunity to add to the WriteMakefile arguments: PREREQ_PM, BUILD_REQUIRES, and TEST_REQUIRES, and therefore modify the prerequisites in the user's MYMETA.yml and MYMETA.json based on conditions found on the user's system.

The dynamic_config field in metadata is already set for you.

You could potentially use this plugin for performing other modifications in Makefile.PL other than user-side prerequisite modifications, but I can't think of a situation where this makes sense. Contact me if you have any ideas!

Only Makefile.PL modification is supported at this time. This author considers the use of Module::Build to be questionable in all circumstances, and Module::Build::Tiny does not (yet?) support dynamic configuration.

CONFIGURATION OPTIONS

-raw

The code to be inserted; must be valid and complete perl statements. You can reference and modify the already-declared %WriteMakefileArgs and %FallbackPrereqs variables, as inserted into Makefile.PL by Dist::Zilla::Plugin::MakeMaker and subclasses (e.g. Dist::Zilla::Plugin::MakeMaker::Awesome since Dist::Zilla 5.001.

This option can be used more than once; lines are added in the order in which they are provided.

This option is pretty low-level; I anticipate its use to be deprecated when better options are added (see below). In particular, the user should not have to be aware of existing code in Makefile.PL nor the exact code required to add prerequisites of various types.

If you use external libraries in the code you are inserting, you must add these modules to configure_requires prereqs in metadata (e.g. via [Prereqs / ConfigureRequires] in your dist.ini).

-delimiter

(Available since version 0.007)

A string, usually a single character, which is stripped from the beginning of all -raw lines. This is because the INI file format strips all leading whitespace from option values, so including this character at the front allows you to use leading whitespace in an option string, so you can indent blocks of code properly.

WARNING: UNSTABLE API!

This plugin is still undergoing active development, and the interfaces will change and grow as I work through the proper way to do various things. As I make changes, I will be using http://grep.cpan.me to find and fix any upstream users, but I obviously cannot do this for DarkPAN users. Regardless, please contact me (see below) and I will keep you directly advised of interface changes.

Future options may include:

  • -condition a Perl expression that is tested before additional prereqs are added

  • -phase the phase in which subsequently-specified module/version pairs will be added

  • -runtime a module and version that is added to runtime prereqs should the -condition be satisfied

  • -test a module and version that is added to test prereqs should the -condition be satisfied

  • -build a module and version that is added to build prereqs should the -condition be satisfied

It is also quite possible that there will be customized condition options, e.g. -can_xs, that will automatically provide common subroutines for use in condition expressions.

SUPPORT

Bugs may be submitted through the RT bug tracker (or bug-Dist-Zilla-Plugin-DynamicPrereqs@rt.cpan.org). I am also usually active on irc, as 'ether' at irc.perl.org.

SEE ALSO

AUTHOR

Karen Etheridge <ether@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2014 by Karen Etheridge.

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