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Module::CPANfile - Parse cpanfile


  use Module::CPANfile;

  my $file = Module::CPANfile->load("cpanfile");
  my $prereqs = $file->prereqs; # CPAN::Meta::Prereqs object

  my @features = $file->features; # CPAN::Meta::Feature objects
  my $merged_prereqs = $file->prereqs_with(@identifiers); # CPAN::Meta::Prereqs



Module::CPANfile is a tool to handle cpanfile format to load application specific dependencies, not just for CPAN distributions.


  $file = Module::CPANfile->load;
  $file = Module::CPANfile->load('cpanfile');

Load and parse a cpanfile. By default it tries to load cpanfile in the current directory, unless you pass the path to its argument.

  $file = Module::CPANfile->from_prereqs({
    runtime => { requires => { DBI => '1.000' } },

Creates a new Module::CPANfile object from prereqs hash you can get via CPAN::Meta's prereqs, or CPAN::Meta::Prereqs' as_string_hash.

  # read MYMETA, then feed the prereqs to create Module::CPANfile
  my $meta = CPAN::Meta->load_file('MYMETA.json');
  my $file = Module::CPANfile->from_prereqs($meta->prereqs);

  # load cpanfile, then recreate it with round-trip
  my $file = Module::CPANfile->load('cpanfile');
  $file = Module::CPANfile->from_prereqs($file->prereq_specs);
                                    # or $file->prereqs->as_string_hash

Returns CPAN::Meta::Prereqs object out of the parsed cpanfile.


Returns a hash reference that should be passed to CPAN::Meta::Prereqs->new.


Returns a list of features available in the cpanfile as CPAN::Meta::Feature.

prereqs_with(@identifiers), effective_prereqs(\@identifiers)

Returns CPAN::Meta::Prereqs object, with merged prereqs for features identified with the @identifiers.


Returns a canonical string (code) representation for cpanfile. Useful if you want to convert CPAN::Meta::Prereqs to a new cpanfile.

  # read MYMETA's prereqs and print cpanfile representation of it
  my $meta = CPAN::Meta->load_file('MYMETA.json');
  my $file = Module::CPANfile->from_prereqs($meta->prereqs);
  print $file->to_string;

By default, it omits the phase where there're no modules registered. If you pass the argument of a true value, it will print them as well.


Saves the currently loaded prereqs as a new cpanfile by calling to_string. Beware this method will overwrite the existing cpanfile without any warning or backup. Taking a backup or giving warnings to users is a caller's responsibility.

  # Read MYMETA.json and creates a new cpanfile
  my $meta = CPAN::Meta->load_file('MYMETA.json');
  my $file = Module::CPANfile->from_prereqs($meta->prereqs);
  $file->merge_meta('MYMETA.json', '2.0');

Merge the effective prereqs with Meta specification loaded from the given META file, using CPAN::Meta. You can specify the META spec version in the second argument, which defaults to 1.4 in case the given file is YAML, and 2 if it is JSON.

  my $options = $file->options_for_module($module);

Returns the extra options specified for a given module as a hash reference. Returns undef when the given module is not specified in the cpanfile.

For example,

  # cpanfile
  requires 'Plack', '1.000',
    dist => "MIYAGAWA/Plack-1.000.tar.gz";

  # ...
  my $file = Module::CPANfile->load;
  my $options = $file->options_for_module('Plack');
  # => { dist => "MIYAGAWA/Plack-1.000.tar.gz" }


Tatsuhiko Miyagawa


cpanfile, CPAN::Meta, CPAN::Meta::Spec