2 package Class::MOP::Package;
7 use Scalar::Util 'blessed';
10 our $VERSION = '0.08';
11 our $AUTHORITY = 'cpan:STEVAN';
13 use base 'Class::MOP::Object';
19 my $package_name = shift;
20 # we hand-construct the class
21 # until we can bootstrap it
24 '$!package' => $package_name,
26 # because of issues with the Perl API
27 # to the typeglob in some versions, we
28 # need to just always grab a new
29 # reference to the hash in the accessor.
30 # Ideally we could just store a ref and
31 # it would Just Work, but oh well :\
32 '%!namespace' => \undef,
39 # all these attribute readers will be bootstrapped
40 # away in the Class::MOP bootstrap section
42 sub name { $_[0]->{'$!package'} }
45 # because of issues with the Perl API
46 # to the typeglob in some versions, we
47 # need to just always grab a new
48 # reference to the hash here. Ideally
49 # we could just store a ref and it would
50 # Just Work, but oh well :\
52 \%{$_[0]->name . '::'}
65 sub _deconstruct_variable_name {
66 my ($self, $variable) = @_;
69 || confess "You must pass a variable name";
71 my $sigil = substr($variable, 0, 1, '');
74 || confess "The variable name must include a sigil";
76 (exists $SIGIL_MAP{$sigil})
77 || confess "I do not recognize that sigil '$sigil'";
79 return ($variable, $sigil, $SIGIL_MAP{$sigil});
85 # ... these functions have to touch the symbol table itself,.. yuk
87 sub add_package_symbol {
88 my ($self, $variable, $initial_value) = @_;
90 my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);
93 no warnings 'redefine', 'misc';
94 *{$self->name . '::' . $name} = ref $initial_value ? $initial_value : \$initial_value;
97 sub remove_package_glob {
98 my ($self, $name) = @_;
100 delete ${$self->name . '::'}{$name};
103 # ... these functions deal with stuff on the namespace level
105 sub has_package_symbol {
106 my ($self, $variable) = @_;
108 my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);
110 return 0 unless exists $self->namespace->{$name};
113 # For some really stupid reason
114 # a typeglob will have a default
115 # value of \undef in the SCALAR
116 # slot, so we need to work around
117 # this. Which of course means that
118 # if you put \undef in your scalar
119 # then this is broken.
121 if (ref($self->namespace->{$name}) eq 'SCALAR') {
122 return ($type eq 'CODE' ? 1 : 0);
124 elsif ($type eq 'SCALAR') {
125 my $val = *{$self->namespace->{$name}}{$type};
126 return defined(${$val}) ? 1 : 0;
129 defined(*{$self->namespace->{$name}}{$type}) ? 1 : 0;
133 sub get_package_symbol {
134 my ($self, $variable) = @_;
136 my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);
138 $self->add_package_symbol($variable)
139 unless exists $self->namespace->{$name};
141 if (ref($self->namespace->{$name}) eq 'SCALAR') {
142 if ($type eq 'CODE') {
144 return \&{$self->name.'::'.$name};
151 return *{$self->namespace->{$name}}{$type};
155 sub remove_package_symbol {
156 my ($self, $variable) = @_;
158 my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);
161 # no doubt this is grossly inefficient and
162 # could be done much easier and faster in XS
164 my ($scalar, $array, $hash, $code);
165 if ($type eq 'SCALAR') {
166 $array = $self->get_package_symbol('@' . $name) if $self->has_package_symbol('@' . $name);
167 $hash = $self->get_package_symbol('%' . $name) if $self->has_package_symbol('%' . $name);
168 $code = $self->get_package_symbol('&' . $name) if $self->has_package_symbol('&' . $name);
170 elsif ($type eq 'ARRAY') {
171 $scalar = $self->get_package_symbol('$' . $name) if $self->has_package_symbol('$' . $name);
172 $hash = $self->get_package_symbol('%' . $name) if $self->has_package_symbol('%' . $name);
173 $code = $self->get_package_symbol('&' . $name) if $self->has_package_symbol('&' . $name);
175 elsif ($type eq 'HASH') {
176 $scalar = $self->get_package_symbol('$' . $name) if $self->has_package_symbol('$' . $name);
177 $array = $self->get_package_symbol('@' . $name) if $self->has_package_symbol('@' . $name);
178 $code = $self->get_package_symbol('&' . $name) if $self->has_package_symbol('&' . $name);
180 elsif ($type eq 'CODE') {
181 $scalar = $self->get_package_symbol('$' . $name) if $self->has_package_symbol('$' . $name);
182 $array = $self->get_package_symbol('@' . $name) if $self->has_package_symbol('@' . $name);
183 $hash = $self->get_package_symbol('%' . $name) if $self->has_package_symbol('%' . $name);
186 confess "This should never ever ever happen";
189 $self->remove_package_glob($name);
191 $self->add_package_symbol(('$' . $name) => $scalar) if defined $scalar;
192 $self->add_package_symbol(('@' . $name) => $array) if defined $array;
193 $self->add_package_symbol(('%' . $name) => $hash) if defined $hash;
194 $self->add_package_symbol(('&' . $name) => $code) if defined $code;
197 sub list_all_package_symbols {
198 my ($self, $type_filter) = @_;
199 return keys %{$self->namespace} unless defined $type_filter;
201 # or we can filter based on
202 # type (SCALAR|ARRAY|HASH|CODE)
203 my $namespace = $self->namespace;
205 (ref($namespace->{$_})
206 ? (ref($namespace->{$_}) eq 'SCALAR' && $type_filter eq 'CODE')
207 : (ref(\$namespace->{$_}) eq 'GLOB'
208 && defined(*{$namespace->{$_}}{$type_filter})));
209 } keys %{$namespace};
220 Class::MOP::Package - Package Meta Object
224 This is an abstraction of a Perl 5 package, it is a superclass of
225 L<Class::MOP::Class> and provides all of the symbol table
226 introspection methods.
234 Returns a metaclass for this package.
236 =item B<initialize ($package_name)>
238 This will initialize a Class::MOP::Package instance which represents
239 the package of C<$package_name>.
243 This is a read-only attribute which returns the package name for the
248 This returns a HASH reference to the symbol table. The keys of the
249 HASH are the symbol names, and the values are typeglob references.
251 =item B<add_package_symbol ($variable_name, ?$initial_value)>
253 Given a C<$variable_name>, which must contain a leading sigil, this
254 method will create that variable within the package which houses the
255 class. It also takes an optional C<$initial_value>, which must be a
256 reference of the same type as the sigil of the C<$variable_name>
259 =item B<get_package_symbol ($variable_name)>
261 This will return a reference to the package variable in
264 =item B<has_package_symbol ($variable_name)>
266 Returns true (C<1>) if there is a package variable defined for
267 C<$variable_name>, and false (C<0>) otherwise.
269 =item B<remove_package_symbol ($variable_name)>
271 This will attempt to remove the package variable at C<$variable_name>.
273 =item B<remove_package_glob ($glob_name)>
275 This will attempt to remove the entire typeglob associated with
276 C<$glob_name> from the package.
278 =item B<list_all_package_symbols (?$type_filter)>
280 This will list all the glob names associated with the current package.
281 By inspecting the globs returned you can discern all the variables in
284 By passing a C<$type_filter>, you can limit the list to only those
285 which match the filter (either SCALAR, ARRAY, HASH or CODE).
291 Stevan Little E<lt>stevan@iinteractive.comE<gt>
293 =head1 COPYRIGHT AND LICENSE
295 Copyright 2006-2008 by Infinity Interactive, Inc.
297 L<http://www.iinteractive.com>
299 This library is free software; you can redistribute it and/or modify
300 it under the same terms as Perl itself.