=head1 NAME

base - Establish IS-A relationship with base class at compile time

=head1 SYNOPSIS

    package Baz;
    use base qw(Foo Bar);

    ## new usage allowed by podmaster, allows for require MODULE versi
+onnumber;
    package Baz;
    use base { Foo => 1, 'Foo::Bar' => 2}; ## need quotes
    use base \%{{ BARE::WORD => 2}}; ## only works like this

=head1 DESCRIPTION

Roughly similar in effect to

    BEGIN {
    require Foo;
    require Bar;
    push @ISA, qw(Foo Bar);
    }

Will also initialize the %FIELDS hash if one of the base classes has
it.  Multiple inheritance of %FIELDS is not supported.  The 'base'
pragma will croak if multiple base classes have a %FIELDS hash.  See
L<fields> for a description of this feature.

When strict 'vars' is in scope I<base> also let you assign to @ISA
without having to declare @ISA with the 'vars' pragma first.

If any of the base classes are not loaded yet, I<base> silently
C<require>s them.  Whether to C<require> a base class package is
determined by the absence of a global $VERSION in the base package.
If $VERSION is not detected even after loading it, <base> will
define $VERSION in the base package, setting it to the string
C<-1, set by base.pm>.

The new feature of this module, allows for version checking via

    use base { 'MODULE' => 33 }; # version 33

which is roughly equivalent to

    use MODULE 33;
    use base 'MODULE';

and will C<croak> much like C<perl -MMODULE=33 -e 1>
if version 33 of MODULE is not available

=head1 HISTORY

This module was introduced with Perl 5.004_04.

=head1 SEE ALSO

L<fields>

=cut

package base;

use 5.006_001;
our $VERSION = "1.02";

sub import {
    my $class = shift;
    my $fields_base;
    my $pkg = caller(0);
    my @bases = @_; ##podmaster - cause i don't wanna modify @bases
    my %BASV=();      ##podmaster

    if(ref $bases[0] eq 'HASH') { ##podmaster
        %BASV = %{$bases[0]};
        @bases = keys %BASV;
    }

    foreach my $base (@bases) { ##podmaster
    next if $pkg->isa($base);
    push @{"$pkg\::ISA"}, $base;
        my $vglob;
    unless (${*{"$base\::VERSION"}{SCALAR}}) {
        eval "require $base";
        # Only ignore "Can't locate" errors from our eval require.
        # Other fatal errors (syntax etc) must be reported.
        die if $@ && $@ !~ /^Can't locate .*? at \(eval /;
        unless (%{"$base\::"}) {
        require Carp;
        Carp::croak("Base class package \"$base\" is empty.\n",
                "\t(Perhaps you need to 'use' the module ",
                "which defines that package first.)");
        }
        ${"$base\::VERSION"} = "-1, set by base.pm"
        unless ${*{"$base\::VERSION"}{SCALAR}};
    }

##podmaster - allows for use base { module => versionnumber }
    if(%BASV and exists $BASV{$base}
            and $BASV{$base} > ${"${base}::VERSION"}) { ## wanted > av
+ailable
        require Carp;
        Carp::croak("$base version $BASV{$base} required--this is only
+ version "
                   .${"${base}::VERSION"});
    }

    # A simple test like (defined %{"$base\::FIELDS"}) will
    # sometimes produce typo warnings because it would create
    # the hash if it was not present before.
    my $fglob;
    if ($fglob = ${"$base\::"}{"FIELDS"} and *$fglob{HASH}) {
        if ($fields_base) {
        require Carp;
        Carp::croak("Can't multiply inherit %FIELDS");
        } else {
        $fields_base = $base;
        }
    }
    }
    if ($fields_base) {
    require fields;
    fields::inherit($pkg, $fields_base);
    }
}

1;
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