NAME

Package::Alias - Alias one namespace as another

VERSION

version 0.13

SYNOPSIS

  use Package::Alias 
      Foo    => 'main',
      'P::Q' => 'Really::Long::Package::Name',
      Alias  => 'Existing::Namespace';

DESCRIPTION

This module aliases one package name to another. After running the SYNOPSIS code, @INC (shorthand for @main::INC) and @Foo::INC reference the same memory, likewise for the other pairings.

Modules not currently loaded into %INC will be used automatically. e.g.,

  use Package::Alias HMS => 'Hash::Merge::Simple'; # automatically runs 'use Hash::Merge::Simple;'

To facilitate some crafty slight of hand, the above will also use P::Q if it's not already loaded, and tell Perl that Really::Long::Package::Name is loaded. In some rare cases such as Mouse, additional trickery may be required; see "Working with Mouse".

GLOBALS

Package::Alias won't alias over a namespace if it's already in use. That's not a fatal error - you'll see a warning and flow will continue. You can change that cowardly behaviour this way:

  # Make Bar like Foo, even if Bar is already in use.

  BEGIN { $Package::Alias::BRAVE = 1 }

  use Package::Alias Bar => 'Foo'; # The old Bar was just clobbered

METHODS

alias

Underlying class method that aliases one namespace to another.

  Package::Alias->alias($aliased_namespace, $original_namespace);

CAVEATS

To be strict-compliant, you'll need to quote any packages on the left-hand side of a => if the namespace has colons. Packages on the right-hand side all have to be quoted. This is documented as "Comma Operator" in perlop.

NOTES

Chip Salzenberg says that it's not technically feasible to perform runtime namespace aliasing. At compile time, Perl grabs pointers to functions and global vars. Those pointers aren't updated if we alias the namespace at runtime.

Working with Mouse

  BEGIN {
    use Package::Alias Moose => Mouse;

    # Make Mouse's finicky internal checks happy...
    Moose::Exporter->setup_import_methods(exporting_package => 'Moose',

        # Alas the defaults live in Mouse...
        as_is => [qw(
                extends with
                has
                before after around
                override super
                augment  inner
            ),
            \&Scalar::Util::blessed,
            \&Carp::confess,
        ],
    );

SEE ALSO

aliased namespace Devel::Symdump

AUTHORS

• Joshua Keroes <joshua@cpan.org>

• Jerrad Pierce <jpierce@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2013 by Joshua Keroes.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

cpanm Package::Alias

perl -MCPAN -e shell
install Package::Alias