package B;
use AllSubsFrom 'A';
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# AllSubsFrom.pm - Perl module to allow importing of all subroutines f
+rom
# another package or packages.
#
# By Ned Konz, perl@bike-nomad.com
#
# Usage:
#
#     package X;
#     use AllSubsFrom qw(A B C);
#
# can also be called explicitly on any package:
#
#    MyPackage->importAllSubsFrom('SomeOtherPackage');
#
#    MyPackage->importAllSubsFrom qw(SomeOtherPackage YetAnotherPackag
+e);
#
use strict;

package AllSubsFrom;
$AllSubsFrom::VERSION = '0.1';

# calls AllSubsFrom::import('A', 'B', 'C');
sub import
{
    UNIVERSAL::importAllSubsFrom( caller, @_ );
}

# This is in UNIVERSAL, the root of all evil.
# That way, it can be called as a class method on any package.

# Export all the not-already-defined subroutines from one
# package to another package:
#     To->importAllSubsFrom('From1', 'From2');
#     importAllSubsFrom('To', 'From1', 'From2');
sub UNIVERSAL::importAllSubsFrom
{
    my $to = shift;

    foreach my $from (@_)
    {
        no strict 'refs';    # to put it mildly.
        my $fromSymtab = \%{ 'main::' . $from . '::' };

        foreach my $key ( keys %$fromSymtab )
        {

            # avoid dangerous subs
            next if $key =~ m{^(?:BEGIN|END|INIT|CHECK|AUTOLOAD|DESTRO
+Y|__.*)$};
            my $codeRef = *{ $from . '::' . $key }{CODE};
            next if !defined($codeRef)                      # symbol b
+ut no sub
              || defined( *{ $to . '::' . $key }{CODE} );   # don't cl
+obber dest
            *{ $to . '::' . $key } = $codeRef;    # replace just the C
+ODE ref
        }
    }
}

# This imports all the subs to the caller's package
#     From->exportAllSubsToMe;
sub UNIVERSAL::exportAllSubsToMe
{
    UNIVERSAL::importAllSubsFrom( caller, shift );
}

"now wasn't that an exciting trip?";
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