NAME

MOP - A Meta Object Protocol for Perl 5

VERSION

version 0.08

SYNOPSIS

  use MOP;

  my $m = MOP::Class->new( 'Foo' );

  printf 'Introspecting %s package with version %s', $m->name, $m->version;

  foreach my $s ( $m->all_slots ) {
      printf 'Found slot %s', $s->name;
  }

  foreach my $m ( $m->all_methods ) {
      printf 'Found method %s', $m->name;
  }

DESCRIPTION

This module implements a Meta Object Protocol for Perl 5 with minimal overhead and no non-core dependencies (eventually).

A Meta Object Protocol, or MOP, is an API to the various parts of the an object system.

CONCEPTS

There are only a few key concepts in the MOP, which are described below.

MOP::Role

A role is simply a package which may have methods, may have slot defintions, and may consume other roles.

MOP::Class

A class does all the things a role does, with the addition of inheritance and instance construction.

MOP::Slot

A slot is best thought of as representing a single entry in the package scoped %HAS variable. This is basically just building upon the conceptual model laid out by UNIVERSAL::Object.

MOP::Method

A method is simply a wrapper around a reference to a CODE slot inside a given package.

SEE ALSO

UNIVERSAL::Object

This module uses the UNIVERSAL::Object module as the chosen instance construction protocol, but also in its introspection assumes that a class uses the conventions of UNIVERSAL::Object specifically with regards to slot storage.

Class::MOP

Almost 10 years ago I wrote Class::MOP, whose purpose was also to bring a MOP to Perl 5. While these modules may have had the same goal, they have different requirements and priorities and so shouldn't be compared directly.

AUTHOR

Stevan Little <stevan@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2017 by Stevan Little.

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