1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210
|
#
# This file is part of MooseX-AbstractMethod
#
# This software is Copyright (c) 2011 by Chris Weyl.
#
# This is free software, licensed under:
#
# The GNU Lesser General Public License, Version 2.1, February 1999
#
package MooseX::AbstractMethod;
{
$MooseX::AbstractMethod::VERSION = '0.004';
}
# ABSTRACT: Declare methods requirements that must be satisfied
use Moose 0.94 ();
use namespace::autoclean;
use Moose::Exporter;
use Moose::Util::MetaRole;
# debugging...
#use Smart::Comments;
{
package MooseX::AbstractMethod::Trait::Class;
{
$MooseX::AbstractMethod::Trait::Class::VERSION = '0.004';
}
use Moose::Role;
use namespace::autoclean;
use Moose::Util qw{ does_role english_list };
sub abstract_method_metaclass {
my $self = shift @_;
return Moose::Meta::Class
->create_anon_class(
# XXX should this just be Moose::Meta::Method as the superclass??
superclasses => [ $self->method_metaclass ],
roles => [ 'MooseX::AbstractMethod::Trait::Method' ],
cache => 1,
)
->name
;
}
sub add_abstract_method {
my ($self, @names) = @_;
my $abstract_meta = $self->abstract_method_metaclass;
for my $name (@names) {
my $method = $abstract_meta->wrap(
sub { Moose->throw_error("Method $name is not implemented!") },
name => $name,
package_name => $self->name,
);
$self->add_method($name => $method);
}
return;
}
# blow up if we're being asked to become immutable, we're a subclasss,
# and we don't implement an abstract method
before make_immutable => sub {
my $self = shift @_;
my @abstract_methods = sort
map { $_->name . ' (from ' . $_->original_package_name . ')' }
grep { $_->original_package_name ne $self->name }
grep { does_role($_, 'MooseX::AbstractMethod::Trait::Method') }
$self->get_all_methods
;
Moose->throw_error(
'These abstract methods have not been implemented in '
. $self->name . ': '
. english_list(@abstract_methods)
) if @abstract_methods;
return;
};
}
{
package MooseX::AbstractMethod::Trait::Method;
{
$MooseX::AbstractMethod::Trait::Method::VERSION = '0.004';
}
use Moose::Role;
use namespace::autoclean;
# well, hello there handsome :)
}
sub abstract { _abstract(@_) }
sub requires { _abstract(@_) }
sub _abstract {
### meta isa: ref $_[0]
return shift->add_abstract_method(@_)
unless $_[0]->isa('Moose::Meta::Role');
goto \&Moose::Role::requires;
}
Moose::Exporter->setup_import_methods(
with_meta => [ qw{ abstract requires } ],
trait_aliases => [
[ 'MooseX::AbstractMethod::Trait::Method' => 'AbstractMethod' ],
],
class_metaroles => {
class => [ 'MooseX::AbstractMethod::Trait::Class' ],
},
);
!!42;
__END__
=pod
=encoding utf-8
=for :stopwords Chris Weyl
=head1 NAME
MooseX::AbstractMethod - Declare methods requirements that must be satisfied
=head1 VERSION
This document describes version 0.004 of MooseX::AbstractMethod - released August 31, 2012 as part of MooseX-AbstractMethod.
=head1 SYNOPSIS
use Moose;
use MooseX::Abstract;
requires 'bar';
# synonm to 'requires'
abstract 'foo';
=head1 DESCRIPTION
This extensions allows classes to flag certain methods as being required to be
implemented by a subclass, much as a L<Moose::Role> does with 'requires'.
=head1 USAGE
As in the synopsis, simply mark certain methods as being required by
subclasses by passing their names to "abstract" or "requires". This will
cause a method of the same name to be installed in the class that will die
horribly if it's ever called. Additionally, when a class is made immutable,
all of its methods are checked to see if they're marked as abstract; if any
abstract methods exists that were not created in the current class, we die
horribly.
Checking for method satisfaction on make_immutable isn't perfect, but AFAICT
it's the most reasonable approach possible at the moment. (Corrections
welcome.)
=head1 NEW SUGAR
=head2 abstract
abstract() allows one to declare a method dependency that must be satisfied by a
subclass before it is invoked, and before the subclass is made immutable.
abstract 'method_name_that_must_be_satisfied';
=head2 requires
requires() is a synonym for abstract() and works in the way you'd expect.
=head1 SOURCE
The development version is on github at L<http://github.com/RsrchBoy/moosex-abstractmethod>
and may be cloned from L<git://github.com/RsrchBoy/moosex-abstractmethod.git>
=head1 BUGS
Please report any bugs or feature requests on the bugtracker website
https://github.com/RsrchBoy/moosex-abstractmethod/issues
When submitting a bug or request, please include a test-file or a
patch to an existing test-file that illustrates the bug or desired
feature.
=head1 AUTHOR
Chris Weyl <cweyl@alumni.drew.edu>
=head1 COPYRIGHT AND LICENSE
This software is Copyright (c) 2011 by Chris Weyl.
This is free software, licensed under:
The GNU Lesser General Public License, Version 2.1, February 1999
=cut
|