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MSCHWERN / your-1.00 / lib / your.pm 

            

              
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package your;
require 5.004;
use strict qw(vars subs);
use vars qw($VERSION);
$VERSION = '1.00';
=head1 NAME
your - Perl pragma to declare use of other package's variables
=head1 SYNOPSIS
    use your qw($Foo::bar @Moo::you %This::that);
=head1 DESCRIPTION
You should use variables from other packages with care, but as long as
you're going to, it doesn't hurt to predeclare it.
Currently, if you use another package's variables and only use it
once, Perl will throw a "variable used only once" warning.  vars.pm
won't allow you to declare other package's variables, and there are
various hack to get around that.  This package lets you declare "Yes,
I am going to use someone else's variables!"
    use Foo;
    use your qw($Foo::magic);
    print $Foo::magic;
=cut
sub import {
    my $caller = caller;
    my($class, @imports) = @_;
    foreach my $sym (@imports) {
        my($type, $name) = unpack('a1a*', $sym);
        unless( $name =~ /::/ ) {
            require Carp;
            Carp::croak("Can only declare other package's variables");
        }
        if( $name =~ tr/A-Za-z_0-9://c ) {
            if( $sym =~ /^\w+[\[{].*[\]}]$/ ) {
                require Carp;
                Carp::croak("Can't declare individual elements of a hash or array");
            }
            elsif ( $^H &= strict::bits('vars') ) {
                require Carp;
                Carp::croak("'$sym' is not a valid variable name under strict vars");
            }
        }
        *$name =
          (  $type eq "\$" ? \$$name
           : $type eq "\@" ? \@$name
           : $type eq "\%" ? \%$name
           : $type eq "\*" ? \*$name
           : $type eq "\&" ? \&$name
            : do {
                require Carp;
                Carp::croak("'$sym' is not a valid variable name");
            });
    }
}
=head1 AUTHOR
Michael G Schwern <schwern@pobox.com>
=head1 COPYRIGHT
Copyright 2001, 2007 by Michael G Schwern E<lt>schwern@pobox.comE<gt>.
This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
See F<http://dev.perl.org/licenses/>
=head1 SEE ALSO
L<vars>, L<perlfunc/our>, L<perlfunc/my>, L<strict>
=cut
1;