# CPAN::Meta::Merge - phpMan

## NAME
    [CPAN::Meta::Merge] - Merging CPAN Meta fragments

## VERSION
    version 2.150010

## SYNOPSIS
     my $merger = [CPAN::Meta::Merge]->new(default_version => "2");
     my $meta = $merger->merge($base, @additional);

## DESCRIPTION
## METHODS
  new
    This creates a [CPAN::Meta::Merge] object. It takes one mandatory named
    argument, "version", declaring the version of the meta-spec that must be
    used for the merge. It can optionally take an "extra_mappings" argument
    that allows one to add additional merging functions for specific
    elements.

    The "extra_mappings" arguments takes a hash ref with the same type of
    structure as described in [CPAN::Meta::Spec], except with its values as
    one of the defined merge strategies or a code ref to a merging function.

      my $merger = [CPAN::Meta::Merge]->new(
          default_version => '2',
          extra_mappings => {
              'optional_features' => \&custom_merge_function,
              'x_custom' => 'set_addition',
              'x_meta_meta' => {
                  name => 'identical',
                  tags => 'set_addition',
              }
          }
      );

  merge(@fragments)
    Merge all @fragments together. It will accept both [CPAN::Meta] objects
    and (possibly incomplete) hashrefs of metadata.

## MERGE STRATEGIES
    "merge" uses various strategies to combine different elements of the
    [CPAN::Meta] objects. The following strategies can be used with the
    extra_mappings argument of "new":

    identical
        The elements must be identical

    set_addition
        The union of two array refs

          [ a, b ] U [ a, c]  = [ a, b, c ]

    uniq_map
        Key value pairs from the right hash are merged to the left hash. Key
        collisions are only allowed if their values are the same. This merge
        function will recurse into nested hash refs following the same merge
        rules.

    improvise
        This merge strategy will try to pick the appropriate predefined
        strategy based on what element type. Array refs will try to use the
        "set_addition" strategy, Hash refs will try to use the "uniq_map"
        strategy, and everything else will try the "identical" strategy.

## AUTHORS
    *   David Golden <<dagolden@cpan.org>>

    *   Ricardo Signes <<rjbs@cpan.org>>

    *   Adam Kennedy <<adamk@cpan.org>>

## COPYRIGHT AND LICENSE
    This software is copyright (c) 2010 by David Golden, Ricardo Signes,
    Adam Kennedy and Contributors.

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