2 package Class::MOP::Package;
7 use Scalar::Util 'blessed', 'reftype';
10 our $VERSION = '0.89';
11 $VERSION = eval $VERSION;
12 our $AUTHORITY = 'cpan:STEVAN';
14 use base 'Class::MOP::Object';
19 my ( $class, @args ) = @_;
21 unshift @args, "package" if @args % 2;
24 my $package_name = $options{package};
27 # we hand-construct the class
28 # until we can bootstrap it
29 if ( my $meta = Class::MOP::get_metaclass_by_name($package_name) ) {
32 my $meta = ( ref $class || $class )->_new({
33 'package' => $package_name,
37 Class::MOP::store_metaclass_by_name($package_name, $meta);
44 my ( $class, @args ) = @_;
46 unshift @args, "package" if @args % 2;
49 my $package_name = delete $options{package};
51 (defined $package_name && $package_name && !blessed($package_name))
52 || confess "You must pass a package name and it cannot be blessed";
54 Class::MOP::remove_metaclass_by_name($package_name);
56 $class->initialize($package_name, %options); # call with first arg form for compat
62 return Class::MOP::Class->initialize($class)->new_object(@_)
63 if $class ne __PACKAGE__;
65 my $params = @_ == 1 ? $_[0] : {@_};
68 package => $params->{package},
71 # because of issues with the Perl API
72 # to the typeglob in some versions, we
73 # need to just always grab a new
74 # reference to the hash in the accessor.
75 # Ideally we could just store a ref and
76 # it would Just Work, but oh well :\
86 # all these attribute readers will be bootstrapped
87 # away in the Class::MOP bootstrap section
91 # because of issues with the Perl API
92 # to the typeglob in some versions, we
93 # need to just always grab a new
94 # reference to the hash here. Ideally
95 # we could just store a ref and it would
96 # Just Work, but oh well :\
98 \%{$_[0]->{'package'} . '::'}
111 sub _deconstruct_variable_name {
112 my ($self, $variable) = @_;
115 || confess "You must pass a variable name";
117 my $sigil = substr($variable, 0, 1, '');
120 || confess "The variable name must include a sigil";
122 (exists $SIGIL_MAP{$sigil})
123 || confess "I do not recognize that sigil '$sigil'";
125 return ($variable, $sigil, $SIGIL_MAP{$sigil});
131 # ... these functions have to touch the symbol table itself,.. yuk
133 sub remove_package_glob {
134 my ($self, $name) = @_;
135 delete $self->namespace->{$name};
138 sub remove_package_symbol {
139 my ($self, $variable) = @_;
141 my ($name, $sigil, $type) = ref $variable eq 'HASH'
142 ? @{$variable}{qw[name sigil type]}
143 : $self->_deconstruct_variable_name($variable);
146 # no doubt this is grossly inefficient and
147 # could be done much easier and faster in XS
149 my ($scalar_desc, $array_desc, $hash_desc, $code_desc) = (
150 { sigil => '$', type => 'SCALAR', name => $name },
151 { sigil => '@', type => 'ARRAY', name => $name },
152 { sigil => '%', type => 'HASH', name => $name },
153 { sigil => '&', type => 'CODE', name => $name },
156 my ($scalar, $array, $hash, $code);
157 if ($type eq 'SCALAR') {
158 $array = $self->get_package_symbol($array_desc) if $self->has_package_symbol($array_desc);
159 $hash = $self->get_package_symbol($hash_desc) if $self->has_package_symbol($hash_desc);
160 $code = $self->get_package_symbol($code_desc) if $self->has_package_symbol($code_desc);
162 elsif ($type eq 'ARRAY') {
163 $scalar = $self->get_package_symbol($scalar_desc) if $self->has_package_symbol($scalar_desc);
164 $hash = $self->get_package_symbol($hash_desc) if $self->has_package_symbol($hash_desc);
165 $code = $self->get_package_symbol($code_desc) if $self->has_package_symbol($code_desc);
167 elsif ($type eq 'HASH') {
168 $scalar = $self->get_package_symbol($scalar_desc) if $self->has_package_symbol($scalar_desc);
169 $array = $self->get_package_symbol($array_desc) if $self->has_package_symbol($array_desc);
170 $code = $self->get_package_symbol($code_desc) if $self->has_package_symbol($code_desc);
172 elsif ($type eq 'CODE') {
173 $scalar = $self->get_package_symbol($scalar_desc) if $self->has_package_symbol($scalar_desc);
174 $array = $self->get_package_symbol($array_desc) if $self->has_package_symbol($array_desc);
175 $hash = $self->get_package_symbol($hash_desc) if $self->has_package_symbol($hash_desc);
178 confess "This should never ever ever happen";
181 $self->remove_package_glob($name);
183 $self->add_package_symbol($scalar_desc => $scalar) if defined $scalar;
184 $self->add_package_symbol($array_desc => $array) if defined $array;
185 $self->add_package_symbol($hash_desc => $hash) if defined $hash;
186 $self->add_package_symbol($code_desc => $code) if defined $code;
189 sub list_all_package_symbols {
190 my ($self, $type_filter) = @_;
192 my $namespace = $self->namespace;
193 return keys %{$namespace} unless defined $type_filter;
196 # or we can filter based on
197 # type (SCALAR|ARRAY|HASH|CODE)
198 if ( $type_filter eq 'CODE' ) {
200 (ref($namespace->{$_})
201 ? (ref($namespace->{$_}) eq 'SCALAR')
202 : (ref(\$namespace->{$_}) eq 'GLOB'
203 && defined(*{$namespace->{$_}}{CODE})));
204 } keys %{$namespace};
206 return grep { *{$namespace->{$_}}{$type_filter} } keys %{$namespace};
218 Class::MOP::Package - Package Meta Object
222 The Package Protocol provides an abstraction of a Perl 5 package. A
223 package is basically namespace, and this module provides methods for
224 looking at and changing that namespace's symbol table.
230 =item B<< Class::MOP::Package->initialize($package_name) >>
232 This method creates a new C<Class::MOP::Package> instance which
233 represents specified package. If an existing metaclass object exists
234 for the package, that will be returned instead.
236 =item B<< Class::MOP::Package->reinitialize($package_name) >>
238 This method forcibly removes any existing metaclass for the package
239 before calling C<initialize>
241 Do not call this unless you know what you are doing.
243 =item B<< $metapackage->name >>
245 This is returns the package's name, as passed to the constructor.
247 =item B<< $metapackage->namespace >>
249 This returns a hash reference to the package's symbol table. The keys
250 are symbol names and the values are typeglob references.
252 =item B<< $metapackage->add_package_symbol($variable_name, $initial_value) >>
254 This method accepts a variable name and an optional initial value. The
255 C<$variable_name> must contain a leading sigil.
257 This method creates the variable in the package's symbol table, and
258 sets it to the initial value if one was provided.
260 =item B<< $metapackage->get_package_symbol($variable_name) >>
262 Given a variable name, this method returns the variable as a reference
263 or undef if it does not exist. The C<$variable_name> must contain a
266 =item B<< $metapackage->has_package_symbol($variable_name) >>
268 Returns true if there is a package variable defined for
269 C<$variable_name>. The C<$variable_name> must contain a leading sigil.
271 =item B<< $metapackage->remove_package_symbol($variable_name) >>
273 This will remove the package variable specified C<$variable_name>. The
274 C<$variable_name> must contain a leading sigil.
276 =item B<< $metapackage->remove_package_glob($glob_name) >>
278 Given the name of a glob, this will remove that glob from the
279 package's symbol table. Glob names do not include a sigil. Removing
280 the glob removes all variables and subroutines with the specified
283 =item B<< $metapackage->list_all_package_symbols($type_filter) >>
285 This will list all the glob names associated with the current
286 package. These names do not have leading sigils.
288 You can provide an optional type filter, which should be one of
289 'SCALAR', 'ARRAY', 'HASH', or 'CODE'.
291 =item B<< $metapackage->get_all_package_symbols($type_filter) >>
293 This works much like C<list_all_package_symbols>, but it returns a
294 hash reference. The keys are glob names and the values are references
295 to the value for that name.
297 =item B<< Class::MOP::Package->meta >>
299 This will return a L<Class::MOP::Class> instance for this class.
305 Stevan Little E<lt>stevan@iinteractive.comE<gt>
307 =head1 COPYRIGHT AND LICENSE
309 Copyright 2006-2009 by Infinity Interactive, Inc.
311 L<http://www.iinteractive.com>
313 This library is free software; you can redistribute it and/or modify
314 it under the same terms as Perl itself.