package Class::MOP::Package; BEGIN { $Class::MOP::Package::AUTHORITY = 'cpan:STEVAN'; } $Class::MOP::Package::VERSION = '2.1204'; use strict; use warnings; use Scalar::Util 'blessed', 'reftype', 'weaken'; use Carp 'confess'; use Devel::GlobalDestruction 'in_global_destruction'; use Module::Runtime 'module_notional_filename'; use Package::Stash; use parent 'Class::MOP::Object'; use Moose::Util 'throw_exception'; # creation ... sub initialize { my ( $class, @args ) = @_; unshift @args, "package" if @args % 2; my %options = @args; my $package_name = delete $options{package}; # we hand-construct the class until we can bootstrap it if ( my $meta = Class::MOP::get_metaclass_by_name($package_name) ) { return $meta; } else { my $meta = ( ref $class || $class )->_new({ 'package' => $package_name, %options, }); Class::MOP::store_metaclass_by_name($package_name, $meta); Class::MOP::weaken_metaclass($package_name) if $options{weaken}; return $meta; } } sub reinitialize { my ( $class, @args ) = @_; unshift @args, "package" if @args % 2; my %options = @args; my $package_name = delete $options{package}; (defined $package_name && $package_name && (!blessed $package_name || $package_name->isa('Class::MOP::Package'))) || throw_exception( MustPassAPackageNameOrAnExistingClassMOPPackageInstance => params => \%options, class => $class ); $package_name = $package_name->name if blessed $package_name; Class::MOP::remove_metaclass_by_name($package_name); $class->initialize($package_name, %options); # call with first arg form for compat } sub create { my $class = shift; my @args = @_; my $meta = $class->initialize(@args); my $filename = module_notional_filename($meta->name); $INC{$filename} = '(set by Moose)' unless exists $INC{$filename}; return $meta; } ## ANON packages { # NOTE: # this should be sufficient, if you have a # use case where it is not, write a test and # I will change it. my $ANON_SERIAL = 0; my %ANON_PACKAGE_CACHE; # NOTE: # we need a sufficiently annoying prefix # this should suffice for now, this is # used in a couple of places below, so # need to put it up here for now. sub _anon_package_prefix { 'Class::MOP::Package::__ANON__::SERIAL::' } sub is_anon { my $self = shift; no warnings 'uninitialized'; my $prefix = $self->_anon_package_prefix; $self->name =~ /^\Q$prefix/; } sub create_anon { my ($class, %options) = @_; my $cache_ok = delete $options{cache}; $options{weaken} = !$cache_ok unless exists $options{weaken}; my $cache_key; if ($cache_ok) { $cache_key = $class->_anon_cache_key(%options); undef $cache_ok if !defined($cache_key); } if ($cache_ok) { if (defined $ANON_PACKAGE_CACHE{$cache_key}) { return $ANON_PACKAGE_CACHE{$cache_key}; } } my $package_name = $class->_anon_package_prefix . ++$ANON_SERIAL; my $meta = $class->create($package_name, %options); if ($cache_ok) { $ANON_PACKAGE_CACHE{$cache_key} = $meta; weaken($ANON_PACKAGE_CACHE{$cache_key}); } return $meta; } sub _anon_cache_key { my $class = shift; my %options = @_; throw_exception( PackagesAndModulesAreNotCachable => class_name => $class, params => \%options, is_module => 0 ); } sub DESTROY { my $self = shift; return if in_global_destruction(); # it'll happen soon anyway and this just makes things more complicated $self->_free_anon if $self->is_anon; } sub _free_anon { my $self = shift; my $name = $self->name; # Moose does a weird thing where it replaces the metaclass for # class when fixing metaclass incompatibility. In that case, # we don't want to clean out the namespace now. We can detect # that because Moose will explicitly update the singleton # cache in Class::MOP using store_metaclass_by_name, which # means that the new metaclass will already exist in the cache # by this point. # The other options here are that $current_meta can be undef if # remove_metaclass_by_name is called explicitly (since the hash # entry is removed first, and then this destructor is called), # or that $current_meta can be the same as $self, which happens # when the metaclass goes out of scope (since the weak reference # in the metaclass cache won't be freed until after this # destructor runs). my $current_meta = Class::MOP::get_metaclass_by_name($name); return if defined($current_meta) && $current_meta ne $self; my ($first_fragments, $last_fragment) = ($name =~ /^(.*)::(.*)$/); no strict 'refs'; # clear @ISA first, to avoid a memory leak # see https://rt.perl.org/rt3/Public/Bug/Display.html?id=92708 @{$name . '::ISA'} = (); %{$name . '::'} = (); delete ${$first_fragments . '::'}{$last_fragment . '::'}; Class::MOP::remove_metaclass_by_name($name); delete $INC{module_notional_filename($name)}; } } sub _new { my $class = shift; return Class::MOP::Class->initialize($class)->new_object(@_) if $class ne __PACKAGE__; my $params = @_ == 1 ? $_[0] : {@_}; return bless { # Need to quote package to avoid a problem with PPI mis-parsing this # as a package statement. 'package' => $params->{package}, # NOTE: # because of issues with the Perl API # to the typeglob in some versions, we # need to just always grab a new # reference to the hash in the accessor. # Ideally we could just store a ref and # it would Just Work, but oh well :\ namespace => \undef, } => $class; } # Attributes # NOTE: # all these attribute readers will be bootstrapped # away in the Class::MOP bootstrap section sub _package_stash { $_[0]->{_package_stash} ||= Package::Stash->new($_[0]->name) } sub namespace { $_[0]->_package_stash->namespace } # Class attributes # ... these functions have to touch the symbol table itself,.. yuk sub add_package_symbol { my $self = shift; $self->_package_stash->add_symbol(@_); } sub remove_package_glob { my $self = shift; $self->_package_stash->remove_glob(@_); } # ... these functions deal with stuff on the namespace level sub has_package_symbol { my $self = shift; $self->_package_stash->has_symbol(@_); } sub get_package_symbol { my $self = shift; $self->_package_stash->get_symbol(@_); } sub get_or_add_package_symbol { my $self = shift; $self->_package_stash->get_or_add_symbol(@_); } sub remove_package_symbol { my $self = shift; $self->_package_stash->remove_symbol(@_); } sub list_all_package_symbols { my $self = shift; $self->_package_stash->list_all_symbols(@_); } sub get_all_package_symbols { my $self = shift; $self->_package_stash->get_all_symbols(@_); } 1; # ABSTRACT: Package Meta Object __END__ =pod =encoding UTF-8 =head1 NAME Class::MOP::Package - Package Meta Object =head1 VERSION version 2.1204 =head1 DESCRIPTION The Package Protocol provides an abstraction of a Perl 5 package. A package is basically namespace, and this module provides methods for looking at and changing that namespace's symbol table. =head1 METHODS =over 4 =item B<< Class::MOP::Package->initialize($package_name, %options) >> This method creates a new C instance which represents specified package. If an existing metaclass object exists for the package, that will be returned instead. No options are valid at the package level. =item B<< Class::MOP::Package->reinitialize($package, %options) >> This method forcibly removes any existing metaclass for the package before calling C. In contrast to C, you may also pass an existing C instance instead of just a package name as C<$package>. Do not call this unless you know what you are doing. =item B<< Class::MOP::Package->create($package, %options) >> Creates a new C instance which represents the specified package, and also does some initialization of that package. Currently, this just does the same thing as C, but is overridden in subclasses, such as C. =item B<< Class::MOP::Package->create_anon(%options) >> Creates a new anonymous package. Valid keys for C<%options> are: =over 4 =item C If this will be C (the default is C), the instance will be cached in C's metaclass cache. =item C If this is C (the default C when L is C), the instance stored in C's metaclass cache will be weakened, so that the anonymous package will be garbage collected when the returned instance goes out of scope. =back =item B<< $metapackage->is_anon >> Returns true if the package is an anonymous package. =item B<< $metapackage->name >> This is returns the package's name, as passed to the constructor. =item B<< $metapackage->namespace >> This returns a hash reference to the package's symbol table. The keys are symbol names and the values are typeglob references. =item B<< $metapackage->add_package_symbol($variable_name, $initial_value) >> This method accepts a variable name and an optional initial value. The C<$variable_name> must contain a leading sigil. This method creates the variable in the package's symbol table, and sets it to the initial value if one was provided. =item B<< $metapackage->get_package_symbol($variable_name) >> Given a variable name, this method returns the variable as a reference or undef if it does not exist. The C<$variable_name> must contain a leading sigil. =item B<< $metapackage->get_or_add_package_symbol($variable_name) >> Given a variable name, this method returns the variable as a reference. If it does not exist, a default value will be generated if possible. The C<$variable_name> must contain a leading sigil. =item B<< $metapackage->has_package_symbol($variable_name) >> Returns true if there is a package variable defined for C<$variable_name>. The C<$variable_name> must contain a leading sigil. =item B<< $metapackage->remove_package_symbol($variable_name) >> This will remove the package variable specified C<$variable_name>. The C<$variable_name> must contain a leading sigil. =item B<< $metapackage->remove_package_glob($glob_name) >> Given the name of a glob, this will remove that glob from the package's symbol table. Glob names do not include a sigil. Removing the glob removes all variables and subroutines with the specified name. =item B<< $metapackage->list_all_package_symbols($type_filter) >> This will list all the glob names associated with the current package. These names do not have leading sigils. You can provide an optional type filter, which should be one of 'SCALAR', 'ARRAY', 'HASH', or 'CODE'. =item B<< $metapackage->get_all_package_symbols($type_filter) >> This works much like C, but it returns a hash reference. The keys are glob names and the values are references to the value for that name. =item B<< Class::MOP::Package->meta >> This will return a L instance for this class. =back =head1 AUTHORS =over 4 =item * Stevan Little =item * Dave Rolsky =item * Jesse Luehrs =item * Shawn M Moore =item * יובל קוג'מן (Yuval Kogman) =item * Karen Etheridge =item * Florian Ragwitz =item * Hans Dieter Pearcey =item * Chris Prather =item * Matt S Trout =back =head1 COPYRIGHT AND LICENSE This software is copyright (c) 2006 by Infinity Interactive, Inc.. This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. =cut