package Mouse::Exporter; use strict; use warnings; use Carp qw(confess); my %SPEC; my $strict_bits; BEGIN{ $strict_bits = strict::bits(qw(subs refs vars)); } # it must be "require", because Mouse::Util depends on Mouse::Exporter, # which depends on Mouse::Util::import() require Mouse::Util; sub import{ $^H |= $strict_bits; # strict->import; ${^WARNING_BITS} |= $warnings::Bits{all}; # warnings->import; return; } sub setup_import_methods{ my($class, %args) = @_; my $exporting_package = $args{exporting_package} ||= caller(); my($import, $unimport) = $class->build_import_methods(%args); Mouse::Util::install_subroutines($exporting_package, import => $import, unimport => $unimport, export_to_level => sub { my($package, $level, undef, @args) = @_; # the third argument is redundant $package->import({ into_level => $level + 1 }, @args); }, export => sub { my($package, $into, @args) = @_; $package->import({ into => $into }, @args); }, ); return; } sub build_import_methods{ my($class, %args) = @_; my $exporting_package = $args{exporting_package} ||= caller(); $SPEC{$exporting_package} = \%args; # canonicalize args my @export_from; if($args{also}){ my %seen; my @stack = ($exporting_package); while(my $current = shift @stack){ push @export_from, $current; my $also = $SPEC{$current}{also} or next; push @stack, grep{ !$seen{$_}++ } ref($also) ? @{ $also } : $also; } } else{ @export_from = ($exporting_package); } my %exports; my @removables; my @all; my @init_meta_methods; foreach my $package(@export_from){ my $spec = $SPEC{$package} or next; if(my $as_is = $spec->{as_is}){ foreach my $thingy (@{$as_is}){ my($code_package, $code_name, $code); if(ref($thingy)){ $code = $thingy; ($code_package, $code_name) = Mouse::Util::get_code_info($code); } else{ $code_package = $package; $code_name = $thingy; no strict 'refs'; $code = \&{ $code_package . '::' . $code_name }; } push @all, $code_name; $exports{$code_name} = $code; if($code_package eq $package){ push @removables, $code_name; } } } if(my $init_meta = $package->can('init_meta')){ if(!grep{ $_ == $init_meta } @init_meta_methods){ push @init_meta_methods, $init_meta; } } } $args{EXPORTS} = \%exports; $args{REMOVABLES} = \@removables; $args{groups}{all} ||= \@all; if(my $default_list = $args{groups}{default}){ my %default; foreach my $keyword(@{$default_list}){ $default{$keyword} = $exports{$keyword} || confess(qq{The $exporting_package package does not export "$keyword"}); } $args{DEFAULT} = \%default; } else{ $args{groups}{default} ||= \@all; $args{DEFAULT} = $args{EXPORTS}; } if(@init_meta_methods){ $args{INIT_META} = \@init_meta_methods; } return (\&do_import, \&do_unimport); } # the entity of general import() sub do_import { my($package, @args) = @_; my $spec = $SPEC{$package} || confess("The package $package package does not use Mouse::Exporter"); my $into = _get_caller_package(ref($args[0]) ? shift @args : undef); my @exports; my @traits; while(@args){ my $arg = shift @args; if($arg =~ s/^-//){ if($arg eq 'traits'){ push @traits, ref($args[0]) ? @{shift(@args)} : shift(@args); } else { Mouse::Util::not_supported("-$arg"); } } elsif($arg =~ s/^://){ my $group = $spec->{groups}{$arg} || confess(qq{The $package package does not export the group "$arg"}); push @exports, @{$group}; } else{ push @exports, $arg; } } $^H |= $strict_bits; # strict->import; ${^WARNING_BITS} |= $warnings::Bits{all}; # warnings->import; if($spec->{INIT_META}){ my $meta; foreach my $init_meta(@{$spec->{INIT_META}}){ $meta = $package->$init_meta(for_class => $into); } if(@traits){ my $type = (split /::/, ref $meta)[-1]; # e.g. "Class" for "My::Meta::Class" @traits = map{ ref($_) ? $_ : Mouse::Util::resolve_metaclass_alias($type => $_, trait => 1) } @traits; require Mouse::Util::MetaRole; Mouse::Util::MetaRole::apply_metaroles( for => $into, Mouse::Util::is_a_metarole($into->meta) ? (role_metaroles => { role => \@traits }) : (class_metaroles => { class => \@traits }), ); } } elsif(@traits){ Carp::confess("Cannot provide traits when $package does not have an init_meta() method"); } if(@exports){ my @export_table; foreach my $keyword(@exports){ push @export_table, $keyword => ($spec->{EXPORTS}{$keyword} || confess(qq{The $package package does not export "$keyword"}) ); } Mouse::Util::install_subroutines($into, @export_table); } else{ Mouse::Util::install_subroutines($into, %{$spec->{DEFAULT}}); } return; } # the entity of general unimport() sub do_unimport { my($package, $arg) = @_; my $spec = $SPEC{$package} || confess("The package $package does not use Mouse::Exporter"); my $from = _get_caller_package($arg); my $stash = do{ no strict 'refs'; \%{$from . '::'} }; for my $keyword (@{ $spec->{REMOVABLES} }) { next if !exists $stash->{$keyword}; my $gv = \$stash->{$keyword}; if(ref($gv) eq 'GLOB' && *{$gv}{CODE} == $spec->{EXPORTS}{$keyword}){ # make sure it is from us delete $stash->{$keyword}; } } return; } sub _get_caller_package { my($arg) = @_; # We need one extra level because it's called by import so there's a layer # of indirection if(ref $arg){ return defined($arg->{into}) ? $arg->{into} : defined($arg->{into_level}) ? scalar caller(1 + $arg->{into_level}) : scalar caller(1); } else{ return scalar caller(1); } } #sub _spec{ %SPEC } 1; __END__ =head1 NAME Mouse::Exporter - make an import() and unimport() just like Mouse.pm =head1 VERSION This document describes Mouse version 0.50_03 =head1 SYNOPSIS package MyApp::Mouse; use Mouse (); use Mouse::Exporter; Mouse::Exporter->setup_import_methods( as_is => [ 'has_rw', 'other_sugar', \&Some::Random::thing ], also => 'Mouse', ); sub has_rw { my $meta = caller->meta; my ( $name, %options ) = @_; $meta->add_attribute( $name, is => 'rw', %options, ); } # then later ... package MyApp::User; use MyApp::Mouse; has 'name'; has_rw 'size'; thing; no MyApp::Mouse; =head1 DESCRIPTION This module encapsulates the exporting of sugar functions in a C-like manner. It does this by building custom C, C methods for your module, based on a spec you provide. Note that C does not provide the C option, but you can easily get the metaclass by C<< caller->meta >> as L shows. =head1 METHODS =head2 C<< setup_import_methods( ARGS ) >> =head2 C<< build_import_methods( ARGS ) -> (\&import, \&unimport) >> =head1 SEE ALSO L =cut