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==============================================================================
Release of version 0.02 of NEXT
==============================================================================
NAME
NEXT - Pseudo class for method redispatch
DESCRIPTION
NEXT.pm adds a pseudoclass named C<NEXT> to any program that
uses it. If a method C<m> calls C<$self->NEXT::m()>, the call to
C<m> is redispatched as if the calling method had not originally
been found.
In other words, a call to C<$self->NEXT::m()> resumes the
depth-first, left-to-right search of parent classes that
resulted in the original call to C<m>.
Note that this is not the same thing as C<$self->SUPER::m()>, which
begins a new dispatch that is restricted to searching the ancestors
of the current class. C<$self->NEXT::m()> can backtrack past
the current class -- to look for a suitable method in other
ancestors of C<$self> -- whereas C<$self->SUPER::m()> cannot.
An particularly interesting use of redispatch is in
C<AUTOLOAD>'ed methods. If such a method determines that it is
not able to handle a particular call, it may choose to
redispatch that call, in the hope that some other C<AUTOLOAD>
(above it, or to its left) might do better.
Note that it is a fatal error for any method (including C<AUTOLOAD>)
to attempt to redispatch any method except itself. For example:
sub D::oops { $_[0]->NEXT::other_method() } # BANG!
AUTHOR
Damian Conway (damian@conway.org)
COPYRIGHT
Copyright (c) 2000-2001, Damian Conway. All Rights Reserved.
This module is free software. It may be used, redistributed
and/or modified under the same terms as Perl itself.
==============================================================================
CHANGES IN VERSION 0.02
- Fixed setting of $AUTOLOAD in NEXT'd AUTOLOADS (thanks Leonid)
- Changed licence for inclusion in core distribution
==============================================================================
AVAILABILITY
NEXT has been uploaded to the CPAN
and is also available from:
http://www.csse.monash.edu.au/~damian/CPAN/NEXT.tar.gz
==============================================================================
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