package Module::CoreList::Utils;

use strict;
use warnings;
use Module::CoreList;

our $VERSION = '5.20190522';
our %utilities;

sub utilities {
    my $perl = shift;
    $perl = shift if eval { $perl->isa(__PACKAGE__) };
    return unless $perl or exists $utilities{$perl};
    return sort keys %{ $utilities{$perl} };
}

sub _released_order {   # Sort helper, to make '?' sort after everything else
    (substr($Module::CoreList::released{$a}, 0, 1) eq "?")
    ? ((substr($Module::CoreList::released{$b}, 0, 1) eq "?")
        ? 0
        : 1)
    : ((substr($Module::CoreList::released{$b}, 0, 1) eq "?")
        ? -1
        : $Module::CoreList::released{$a} cmp $Module::CoreList::released{$b} )
}

sub first_release_raw {
    my $util = shift;
    $util = shift if eval { $util->isa(__PACKAGE__) };
      #and scalar @_ and $_[0] =~ m#\A[a-zA-Z_][0-9a-zA-Z_]*(?:(::|')[0-9a-zA-Z_]+)*\z#;
    my $version = shift;

    my @perls = $version
        ? grep { exists $utilities{$_}{ $util } &&
                        $utilities{$_}{ $util } ge $version } keys %utilities
        : grep { exists $utilities{$_}{ $util }             } keys %utilities;

    return grep { exists $Module::CoreList::released{$_} } @perls;
}

sub first_release_by_date {
    my @perls = &first_release_raw;
    return unless @perls;
    return (sort _released_order @perls)[0];
}

sub first_release {
    my @perls = &first_release_raw;
    return unless @perls;
    return (sort { $a cmp $b } @perls)[0];
}

sub removed_from {
  my @perls = &removed_raw;
  return shift @perls;
}

sub removed_from_by_date {
  my @perls = sort _released_order &removed_raw;
  return shift @perls;
}

sub removed_raw {
  my $util = shift;
  $util = shift if eval { $util->isa(__PACKAGE__) };
  return unless my @perls = sort { $a cmp $b } first_release_raw($util);
  @perls = grep { exists $Module::CoreList::released{$_} } @perls;
  my $last = pop @perls;
  my @removed = grep { $_ > $last } sort { $a cmp $b } keys %utilities;
  return @removed;
}

my %delta = (
    5 => {
        changed => {
            'a2p'                   => '1',
            'c2ph'                  => '1',
            'cppstdin'              => '1',
            'find2perl'             => '1',
            'pstruct'               => '1',
            's2p'                   => '1',
        },
        removed => {
        }
    },

    5.001 => {
        delta_from => 5,
        changed => {
            'h2xs'                  => '1',
        },
        removed => {
        }
    },

    5.002 => {
        delta_from => 5.001,
        changed => {
            'h2ph'                  => '1',
            'perlbug'               => '1',
            'perldoc'               => '1',
            'pod2html'              => '1',
            'pod2latex'             => '1',
            'pod2man'               => '1',
            'pod2text'              => '1',
        },
        removed => {
        }
    },

    5.00307 => {
        delta_from => 5.002,
        changed => {
            'pl2pm'                 => '1',
        },
        removed => {
           'cppstdin'              => 1,
           'pstruct'               => 1,
        }
    },

    5.004 => {
        delta_from => 5.00307,
        changed => {
            'splain'                => '1',
        },
        removed => {
        }
    },

    5.005 => {
        delta_from => 5.00405,
        changed => {
            'perlcc'                => '1',
        },
        removed => {
        }
    },

    5.00503 => {
        delta_from => 5.005,
        changed => {
        },
        removed => {
        }
    },

    5.00405 => {
        delta_from => 5.004,
        changed => {
        },
        removed => {
        }
    },

    5.006 => {
        delta_from => 5.00504,
        changed => {
            'dprofpp'               => '1',
            'pod2usage'             => '1',
            'podchecker'            => '1',
            'podselect'             => '1',
            'pstruct'               => '1',
        },
        removed => {
        }
    },

    5.006001 => {
        delta_from => 5.006,
        changed => {
        },
        removed => {
        }
    },

    5.007003 => {
        delta_from => 5.006002,
        changed => {
            'libnetcfg'             => '1',
            'perlivp'               => '1',
            'psed'                  => '1',
            'xsubpp'                => '1',
        },
        removed => {
        }
    },

    5.008 => {
        delta_from => 5.007003,
        changed => {
            'enc2xs'                => '1',
            'piconv'                => '1',
        },
        removed => {
        }
    },

    5.008001 => {
        delta_from => 5.008,
        changed => {
            'cpan'                  => '1',
        },
        removed => {
        }
    },

    5.009 => {
        delta_from => 5.008009,
        changed => {
        },
        removed => {
           'corelist'              => 1,
           'instmodsh'             => 1,
           'prove'                 => 1,
        }
    },

    5.008002 => {
        delta_from => 5.008001,
        changed => {
        },
        removed => {
        }
    },

    5.006002 => {
        delta_from => 5.006001,
        changed => {
        },
        removed => {
        }
    },

    5.008003 => {
        delta_from => 5.008002,
        changed => {
            'instmodsh'             => '1',
            'prove'                 => '1',
        },
        removed => {
        }
    },

    5.00504 => {
        delta_from => 5.00503,
        changed => {
        },
        removed => {
        }
    },

    5.009001 => {
        delta_from => 5.009,
        changed => {
            'instmodsh'             => '1',
            'prove'                 => '1',
        },
        removed => {
        }
    },

    5.008004 => {
        delta_from => 5.008003,
        changed => {
        },
        removed => {
        }
    },

    5.008005 => {
        delta_from => 5.008004,
        changed => {
        },
        removed => {
        }
    },

    5.008006 => {
        delta_from => 5.008005,
        changed => {
        },
        removed => {
        }
    },

    5.009002 => {
        delta_from => 5.009001,
        changed => {
            'corelist'              => '1',
        },
        removed => {
        }
    },

    5.008007 => {
        delta_from => 5.008006,
        changed => {
        },
        removed => {
        }
    },

    5.009003 => {
        delta_from => 5.009002,
        changed => {
            'ptar'                  => '1',
            'ptardiff'              => '1',
            'shasum'                => '1',
        },
        removed => {
        }
    },

    5.008008 => {
        delta_from => 5.008007,
        changed => {
        },
        removed => {
        }
    },

    5.009004 => {
        delta_from => 5.009003,
        changed => {
            'config_data'           => '1',
        },
        removed => {
        }
    },

    5.009005 => {
        delta_from => 5.009004,
        changed => {
            'cpan2dist'             => '1',
            'cpanp'                 => '1',
            'cpanp-run-perl'        => '1',
        },
        removed => {
           'perlcc'                => 1,
        }
    },

    5.010000 => {
        delta_from => 5.009005,
        changed => {
        },
        removed => {
        }
    },

    5.008009 => {
        delta_from => 5.008008,
        changed => {
            'corelist'              => '1',
        },
        removed => {
        }
    },

    5.010001 => {
        delta_from => 5.010000,
        changed => {
        },
        removed => {
        }
    },

    5.011 => {
        delta_from => 5.010001,
        changed => {
        },
        removed => {
        }
    },

    5.011001 => {
        delta_from => 5.011,
        changed => {
        },
        removed => {
        }
    },

    5.011002 => {
        delta_from => 5.011001,
        changed => {
            'perlthanks'            => '1',
        },
        removed => {
        }
    },

    5.011003 => {
        delta_from => 5.011002,
        changed => {
        },
        removed => {
        }
    },

    5.011004 => {
        delta_from => 5.011003,
        changed => {
        },
        removed => {
        }
    },

    5.011005 => {
        delta_from => 5.011004,
        changed => {
        },
        removed => {
        }
    },

    5.012 => {
        delta_from => 5.011005,
        changed => {
        },
        removed => {
        }
    },

    5.013 => {
        delta_from => 5.012005,
        changed => {
        },
        removed => {
        }
    },

    5.012001 => {
        delta_from => 5.012,
        changed => {
        },
        removed => {
        }
    },

    5.013001 => {
        delta_from => 5.013,
        changed => {
        },
        removed => {
        }
    },

    5.013002 => {
        delta_from => 5.013001,
        changed => {
        },
        removed => {
        }
    },

    5.013003 => {
        delta_from => 5.013002,
        changed => {
        },
        removed => {
        }
    },

    5.013004 => {
        delta_from => 5.013003,
        changed => {
        },
        removed => {
        }
    },

    5.012002 => {
        delta_from => 5.012001,
        changed => {
        },
        removed => {
        }
    },

    5.013005 => {
        delta_from => 5.013004,
        changed => {
        },
        removed => {
        }
    },

    5.013006 => {
        delta_from => 5.013005,
        changed => {
        },
        removed => {
        }
    },

    5.013007 => {
        delta_from => 5.013006,
        changed => {
            'ptargrep'              => '1',
        },
        removed => {
        }
    },

    5.013008 => {
        delta_from => 5.013007,
        changed => {
        },
        removed => {
        }
    },

    5.013009 => {
        delta_from => 5.013008,
        changed => {
            'json_pp'               => '1',
        },
        removed => {
        }
    },

    5.012003 => {
        delta_from => 5.012002,
        changed => {
        },
        removed => {
        }
    },

    5.013010 => {
        delta_from => 5.013009,
        changed => {
        },
        removed => {
        }
    },

    5.013011 => {
        delta_from => 5.013010,
        changed => {
        },
        removed => {
        }
    },

    5.014 => {
        delta_from => 5.013011,
        changed => {
        },
        removed => {
        }
    },

    5.014001 => {
        delta_from => 5.014,
        changed => {
        },
        removed => {
        }
    },

    5.015 => {
        delta_from => 5.014004,
        changed => {
        },
        removed => {
           'dprofpp'               => 1,
        }
    },

    5.012004 => {
        delta_from => 5.012003,
        changed => {
        },
        removed => {
        }
    },

    5.015001 => {
        delta_from => 5.015,
        changed => {
        },
        removed => {
        }
    },

    5.015002 => {
        delta_from => 5.015001,
        changed => {
        },
        removed => {
        }
    },

    5.015003 => {
        delta_from => 5.015002,
        changed => {
        },
        removed => {
        }
    },

    5.014002 => {
        delta_from => 5.014001,
        changed => {
        },
        removed => {
        }
    },

    5.015004 => {
        delta_from => 5.015003,
        changed => {
        },
        removed => {
        }
    },

    5.015005 => {
        delta_from => 5.015004,
        changed => {
        },
        removed => {
        }
    },

    5.015006 => {
        delta_from => 5.015005,
        changed => {
            'zipdetails'            => '1',
        },
        removed => {
        }
    },

    5.015007 => {
        delta_from => 5.015006,
        changed => {
        },
        removed => {
        }
    },

    5.015008 => {
        delta_from => 5.015007,
        changed => {
        },
        removed => {
        }
    },

    5.015009 => {
        delta_from => 5.015008,
        changed => {
        },
        removed => {
        }
    },

    5.016 => {
        delta_from => 5.015009,
        changed => {
        },
        removed => {
        }
    },

    5.017 => {
        delta_from => 5.016003,
        changed => {
        },
        removed => {
        }
    },

    5.017001 => {
        delta_from => 5.017,
        changed => {
        },
        removed => {
        }
    },

    5.017002 => {
        delta_from => 5.017001,
        changed => {
        },
        removed => {
        }
    },

    5.016001 => {
        delta_from => 5.016,
        changed => {
        },
        removed => {
        }
    },

    5.017003 => {
        delta_from => 5.017002,
        changed => {
        },
        removed => {
        }
    },

    5.017004 => {
        delta_from => 5.017003,
        changed => {
        },
        removed => {
        }
    },

    5.014003 => {
        delta_from => 5.014002,
        changed => {
        },
        removed => {
        }
    },

    5.017005 => {
        delta_from => 5.017004,
        changed => {
        },
        removed => {
        }
    },

    5.016002 => {
        delta_from => 5.016001,
        changed => {
        },
        removed => {
        }
    },

    5.012005 => {
        delta_from => 5.012004,
        changed => {
        },
        removed => {
        }
    },

    5.017006 => {
        delta_from => 5.017005,
        changed => {
        },
        removed => {
        }
    },

    5.017007 => {
        delta_from => 5.017006,
        changed => {
        },
        removed => {
        }
    },

    5.017008 => {
        delta_from => 5.017007,
        changed => {
        },
        removed => {
        }
    },

    5.017009 => {
        delta_from => 5.017008,
        changed => {
        },
        removed => {
        }
    },

    5.014004 => {
        delta_from => 5.014003,
        changed => {
        },
        removed => {
        }
    },

    5.016003 => {
        delta_from => 5.016002,
        changed => {
        },
        removed => {
        }
    },

    5.017010 => {
        delta_from => 5.017009,
        changed => {
        },
        removed => {
        }
    },

    5.017011 => {
        delta_from => 5.017010,
        changed => {
        },
        removed => {
        }
    },
    5.018000 => {
        delta_from => 5.017011,
        changed => {
        },
        removed => {
        }
    },
    5.018001 => {
        delta_from => 5.018000,
        changed => {
        },
        removed => {
        }
    },
    5.018002 => {
        delta_from => 5.018001,
        changed => {
        },
        removed => {
        }
    },
    5.018003 => {
        delta_from => 5.018000,
        changed => {
        },
        removed => {
        }
    },
    5.018004 => {
        delta_from => 5.018000,
        changed => {
        },
        removed => {
        }
    },
    5.019000 => {
        delta_from => 5.018000,
        changed => {
        },
        removed => {
            'cpan2dist'             => '1',
            'cpanp'                 => '1',
            'cpanp-run-perl'        => '1',
            'pod2latex'             => '1',
        }
    },
    5.019001 => {
        delta_from => 5.019000,
        changed => {
        },
        removed => {
        }
    },
    5.019002 => {
        delta_from => 5.019001,
        changed => {
        },
        removed => {
        }
    },
    5.019003 => {
        delta_from => 5.019002,
        changed => {
        },
        removed => {
        }
    },
    5.019004 => {
        delta_from => 5.019003,
        changed => {
        },
        removed => {
        }
    },
    5.019005 => {
        delta_from => 5.019004,
        changed => {
        },
        removed => {
        }
    },
    5.019006 => {
        delta_from => 5.019005,
        changed => {
        },
        removed => {
        }
    },
    5.019007 => {
        delta_from => 5.019006,
        changed => {
        },
        removed => {
        }
    },
    5.019008 => {
        delta_from => 5.019007,
        changed => {
        },
        removed => {
        }
    },
    5.019009 => {
        delta_from => 5.019008,
        changed => {
        },
        removed => {
        }
    },
    5.019010 => {
        delta_from => 5.019009,
        changed => {
        },
        removed => {
        }
    },
    5.019011 => {
        delta_from => 5.019010,
        changed => {
        },
        removed => {
        }
    },
    5.020000 => {
        delta_from => 5.019011,
        changed => {
        },
        removed => {
        }
    },
    5.021000 => {
        delta_from => 5.020000,
        changed => {
        },
        removed => {
        }
    },
    5.021001 => {
        delta_from => 5.021000,
        changed => {
        },
        removed => {
            'a2p'                   => 1,
            'config_data'           => 1,
            'find2perl'             => 1,
            'psed'                  => 1,
            's2p'                   => 1,
        }
    },
    5.021002 => {
        delta_from => 5.021001,
        changed => {
        },
        removed => {
        }
    },
    5.021003 => {
        delta_from => 5.021002,
        changed => {
        },
        removed => {
        }
    },
    5.020001 => {
        delta_from => 5.02,
        changed => {
        },
        removed => {
        }
    },
    5.021004 => {
        delta_from => 5.021003,
        changed => {
        },
        removed => {
        }
    },
    5.021005 => {
        delta_from => 5.021004,
        changed => {
        },
        removed => {
        }
    },
    5.021006 => {
        delta_from => 5.021005,
        changed => {
        },
        removed => {
        }
    },
    5.021007 => {
        delta_from => 5.021006,
        changed => {
        },
        removed => {
        }
    },
    5.021008 => {
        delta_from => 5.021007,
        changed => {
        },
        removed => {
        }
    },
    5.020002 => {
        delta_from => 5.020001,
        changed => {
        },
        removed => {
        }
    },
    5.021009 => {
        delta_from => 5.021008,
        changed => {
            'encguess'              => '1',
        },
        removed => {
        }
    },
    5.021010 => {
        delta_from => 5.021009,
        changed => {
        },
        removed => {
        }
    },
    5.021011 => {
        delta_from => 5.02101,
        changed => {
        },
        removed => {
        }
    },
    5.022000 => {
        delta_from => 5.021011,
        changed => {
        },
        removed => {
        }
    },
    5.023000 => {
        delta_from => 5.022000,
        changed => {
        },
        removed => {
        }
    },
    5.023001 => {
        delta_from => 5.023,
        changed => {
        },
        removed => {
        }
    },
    5.023002 => {
        delta_from => 5.023001,
        changed => {
        },
        removed => {
        }
    },
    5.020003 => {
        delta_from => 5.020002,
        changed => {
        },
        removed => {
        }
    },
    5.023003 => {
        delta_from => 5.023002,
        changed => {
        },
        removed => {
        }
    },
    5.023004 => {
        delta_from => 5.023003,
        changed => {
        },
        removed => {
        }
    },
    5.023005 => {
        delta_from => 5.023004,
        changed => {
        },
        removed => {
        }
    },
    5.022001 => {
        delta_from => 5.022,
        changed => {
        },
        removed => {
        }
    },
    5.023006 => {
        delta_from => 5.023005,
        changed => {
        },
        removed => {
        }
    },
    5.023007 => {
        delta_from => 5.023006,
        changed => {
        },
        removed => {
        }
    },
    5.023008 => {
        delta_from => 5.023007,
        changed => {
        },
        removed => {
        }
    },
    5.023009 => {
        delta_from => 5.023008,
        changed => {
        },
        removed => {
        }
    },
    5.022002 => {
        delta_from => 5.022001,
        changed => {
        },
        removed => {
        }
    },
    5.024000 => {
        delta_from => 5.023009,
        changed => {
        },
        removed => {
        }
    },
    5.025000 => {
        delta_from => 5.024000,
        changed => {
        },
        removed => {
        }
    },
    5.025001 => {
        delta_from => 5.025000,
        changed => {
        },
        removed => {
        }
    },
    5.025002 => {
        delta_from => 5.025001,
        changed => {
        },
        removed => {
        }
    },
    5.025003 => {
        delta_from => 5.025002,
        changed => {
        },
        removed => {
        }
    },
    5.025004 => {
        delta_from => 5.025003,
        changed => {
        },
        removed => {
        }
    },
    5.025005 => {
        delta_from => 5.025004,
        changed => {
        },
        removed => {
        }
    },
    5.025006 => {
        delta_from => 5.025005,
        changed => {
        },
        removed => {
        }
    },
    5.025007 => {
        delta_from => 5.025006,
        changed => {
        },
        removed => {
        }
    },
    5.025008 => {
        delta_from => 5.025007,
        changed => {
        },
        removed => {
        }
    },
    5.022003 => {
        delta_from => 5.022002,
        changed => {
        },
        removed => {
        }
    },
    5.024001 => {
        delta_from => 5.024000,
        changed => {
        },
        removed => {
        }
    },
    5.025009 => {
        delta_from => 5.025008,
        changed => {
        },
        removed => {
            'c2ph'                  => 1,
            'pstruct'               => 1,
        }
    },
    5.025010 => {
        delta_from => 5.025009,
        changed => {
        },
        removed => {
        }
    },
    5.025011 => {
        delta_from => 5.025010,
        changed => {
        },
        removed => {
        }
    },
    5.025012 => {
        delta_from => 5.025011,
        changed => {
        },
        removed => {
        }
    },
    5.026000 => {
        delta_from => 5.025012,
        changed => {
        },
        removed => {
        }
    },
    5.027000 => {
        delta_from => 5.026000,
        changed => {
        },
        removed => {
        }
    },
    5.027001 => {
        delta_from => 5.027000,
        changed => {
        },
        removed => {
        }
    },
    5.022004 => {
        delta_from => 5.022003,
        changed => {
        },
        removed => {
        }
    },
    5.024002 => {
        delta_from => 5.024001,
        changed => {
        },
        removed => {
        }
    },
    5.027002 => {
        delta_from => 5.027001,
        changed => {
        },
        removed => {
        }
    },
    5.027003 => {
        delta_from => 5.027002,
        changed => {
        },
        removed => {
        }
    },
    5.027004 => {
        delta_from => 5.027003,
        changed => {
        },
        removed => {
        }
    },
    5.024003 => {
        delta_from => 5.024002,
        changed => {
        },
        removed => {
        }
    },
    5.026001 => {
        delta_from => 5.026000,
        changed => {
        },
        removed => {
        }
    },
    5.027005 => {
        delta_from => 5.027004,
        changed => {
        },
        removed => {
        }
    },
    5.027006 => {
        delta_from => 5.027005,
        changed => {
        },
        removed => {
        }
    },
    5.027007 => {
        delta_from => 5.027006,
        changed => {
        },
        removed => {
        }
    },
    5.027008 => {
        delta_from => 5.027007,
        changed => {
        },
        removed => {
        }
    },
    5.027009 => {
        delta_from => 5.027008,
        changed => {
        },
        removed => {
        }
    },
    5.027010 => {
        delta_from => 5.027009,
        changed => {
        },
        removed => {
        }
    },
    5.024004 => {
        delta_from => 5.024003,
        changed => {
        },
        removed => {
        }
    },
    5.026002 => {
        delta_from => 5.026001,
        changed => {
        },
        removed => {
        }
    },
    5.027011 => {
        delta_from => 5.027010,
        changed => {
        },
        removed => {
        }
    },
    5.028000 => {
        delta_from => 5.027011,
        changed => {
        },
        removed => {
        }
    },
    5.029000 => {
        delta_from => 5.028,
        changed => {
        },
        removed => {
        }
    },
    5.029001 => {
        delta_from => 5.029000,
        changed => {
        },
        removed => {
        }
    },
    5.029002 => {
        delta_from => 5.029001,
        changed => {
        },
        removed => {
        }
    },
    5.029003 => {
        delta_from => 5.029002,
        changed => {
        },
        removed => {
        }
    },
    5.029004 => {
        delta_from => 5.029003,
        changed => {
        },
        removed => {
        }
    },
    5.029005 => {
        delta_from => 5.029004,
        changed => {
        },
        removed => {
        }
    },
    5.026003 => {
        delta_from => 5.026002,
        changed => {
        },
        removed => {
        }
    },
    5.028001 => {
        delta_from => 5.028000,
        changed => {
        },
        removed => {
        }
    },
    5.029006 => {
        delta_from => 5.029005,
        changed => {
        },
        removed => {
        }
    },
    5.029007 => {
        delta_from => 5.029006,
        changed => {
        },
        removed => {
        }
    },
    5.029008 => {
        delta_from => 5.029007,
        changed => {
        },
        removed => {
        }
    },
    5.029009 => {
        delta_from => 5.029008,
        changed => {
        },
        removed => {
        }
    },
    5.028002 => {
        delta_from => 5.028001,
        changed => {
        },
        removed => {
        }
    },
    5.029010 => {
        delta_from => 5.029009,
        changed => {
        },
        removed => {
        }
    },
    5.030000 => {
        delta_from => 5.029010,
        changed => {
        },
        removed => {
        }
    },
);

%utilities = Module::CoreList::_undelta(\%delta);

# Create aliases with trailing zeros for $] use

$utilities{'5.000'} = $utilities{5};

_create_aliases(\%utilities);

sub _create_aliases {
    my ($hash) = @_;

    for my $version (keys %$hash) {
        next unless $version >= 5.010;

        my $padded = sprintf "%0.6f", $version;

        # If the version in string form isn't the same as the numeric version,
        # alias it.
        if ($padded ne $version && $version == $padded) {
            $hash->{$padded} = $hash->{$version};
        }
    }
}

'foo';

=pod

=head1 NAME

Module::CoreList::Utils - what utilities shipped with versions of perl

=head1 SYNOPSIS

 use Module::CoreList::Utils;

 print $Module::CoreList::Utils::utilities{5.009003}{ptar}; # prints 1

 print Module::CoreList::Utils->first_release('corelist');
 # prints 5.008009

 print Module::CoreList::Utils->first_release_by_date('corelist');
 # prints 5.009002

=head1 DESCRIPTION

Module::CoreList::Utils provides information on which core and dual-life utilities shipped
with each version of L<perl>.

It provides a number of mechanisms for querying this information.

There is a functional programming API available for programmers to query
information.

Programmers may also query the contained hash structure to find relevant
information.

=head1 FUNCTIONS API

These are the functions that are available, they may either be called as functions or class methods:

  Module::CoreList::Utils::first_release('corelist'); # as a function

  Module::CoreList::Utils->first_release('corelist'); # class method

=over

=item C<utilities>

Requires a perl version as an argument, returns a list of utilities that shipped with
that version of perl, or undef/empty list if that perl doesn't exist.

=item C<first_release( UTILITY )>

Requires a UTILITY name as an argument, returns the perl version when that utility first
appeared in core as ordered by perl version number or undef ( in scalar context )
or an empty list ( in list context ) if that utility is not in core.

=item C<first_release_by_date( UTILITY )>

Requires a UTILITY name as an argument, returns the perl version when that utility first
appeared in core as ordered by release date or undef ( in scalar context )
or an empty list ( in list context ) if that utility is not in core.

=item C<removed_from( UTILITY )>

Takes a UTILITY name as an argument, returns the first perl version where that utility
was removed from core. Returns undef if the given utility was never in core or remains
in core.

=item C<removed_from_by_date( UTILITY )>

Takes a UTILITY name as an argument, returns the first perl version by release date where that
utility was removed from core. Returns undef if the given utility was never in core or remains
in core.

=back

=head1 DATA STRUCTURES

These are the hash data structures that are available:

=over

=item C<%Module::CoreList::Utils::utilities>

A hash of hashes that is keyed on perl version as indicated
in $].  The second level hash is utility / defined pairs.

=back

=head1 AUTHOR

Chris C<BinGOs> Williams <chris@bingosnet.co.uk>

Currently maintained by the perl 5 porters E<lt>perl5-porters@perl.orgE<gt>.

This module is the result of archaeology undertaken during QA Hackathon
in Lancaster, April 2013.

=head1 LICENSE

Copyright (C) 2013 Chris Williams.  All Rights Reserved.

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

=head1 SEE ALSO

L<corelist>, L<Module::CoreList>, L<perl>, L<http://perlpunks.de/corelist>

=cut
