package Moose::Meta::Method::Constructor; use strict; use warnings; use Carp (); use Scalar::Util 'blessed', 'weaken', 'looks_like_number', 'refaddr'; our $VERSION = '1.20'; our $AUTHORITY = 'cpan:STEVAN'; use base 'Moose::Meta::Method', 'Class::MOP::Method::Constructor'; sub new { my $class = shift; my %options = @_; my $meta = $options{metaclass}; (ref $options{options} eq 'HASH') || $class->throw_error("You must pass a hash of options", data => $options{options}); ($options{package_name} && $options{name}) || $class->throw_error("You must supply the package_name and name parameters $Class::MOP::Method::UPGRADE_ERROR_TEXT"); my $self = bless { 'body' => undef, 'package_name' => $options{package_name}, 'name' => $options{name}, 'options' => $options{options}, 'associated_metaclass' => $meta, '_expected_method_class' => $options{_expected_method_class} || 'Moose::Object', } => $class; # we don't want this creating # a cycle in the code, if not # needed weaken($self->{'associated_metaclass'}); $self->_initialize_body; return $self; } ## method sub _initialize_body { my $self = shift; # TODO: # the %options should also include a both # a call 'initializer' and call 'SUPER::' # options, which should cover approx 90% # of the possible use cases (even if it # requires some adaption on the part of # the author, after all, nothing is free) my $source = 'sub {'; $source .= "\n" . 'my $_instance = shift;'; $source .= "\n" . 'my $class = Scalar::Util::blessed($_instance) || $_instance;'; $source .= "\n" . "if (\$class ne '" . $self->associated_metaclass->name . "') {"; $source .= "\n return " . $self->_generate_fallback_constructor('$class') . ";"; $source .= "\n}\n"; $source .= $self->_generate_params('$params', '$class'); $source .= $self->_generate_instance('$instance', '$class'); $source .= $self->_generate_slot_initializers; $source .= $self->_generate_triggers(); $source .= ";\n" . $self->_generate_BUILDALL(); $source .= ";\nreturn \$instance"; $source .= ";\n" . '}'; warn $source if $self->options->{debug}; # We need to check if the attribute ->can('type_constraint') # since we may be trying to immutabilize a Moose meta class, # which in turn has attributes which are Class::MOP::Attribute # objects, rather than Moose::Meta::Attribute. And # Class::MOP::Attribute attributes have no type constraints. # However we need to make sure we leave an undef value there # because the inlined code is using the index of the attributes # to determine where to find the type constraint my $attrs = $self->_attributes; my @type_constraints = map { $_->can('type_constraint') ? $_->type_constraint : undef } @$attrs; my @type_constraint_bodies = map { defined $_ ? $_->_compiled_type_constraint : undef; } @type_constraints; my $defaults = [map { $_->default } @$attrs]; my ( $code, $e ) = $self->_compile_code( code => $source, environment => { '$meta' => \$self, '$attrs' => \$attrs, '$defaults' => \$defaults, '@type_constraints' => \@type_constraints, '@type_constraint_bodies' => \@type_constraint_bodies, }, ); $self->throw_error( "Could not eval the constructor :\n\n$source\n\nbecause :\n\n$e", error => $e, data => $source ) if $e; $self->{'body'} = $code; } sub _generate_fallback_constructor { my ( $self, $class_var ) = @_; "${class_var}->Moose::Object::new(\@_)"; } sub _generate_params { my ( $self, $var, $class_var ) = @_; "my $var = " . $self->_generate_BUILDARGS( $class_var, '@_' ) . ";\n"; } sub _generate_instance { my ( $self, $var, $class_var ) = @_; "my $var = " . $self->associated_metaclass->inline_create_instance($class_var) . ";\n"; } sub _generate_slot_initializers { my ($self) = @_; return (join ";\n" => map { $self->_generate_slot_initializer($_) } 0 .. (@{$self->_attributes} - 1)) . ";\n"; } sub _generate_BUILDARGS { my ( $self, $class, $args ) = @_; my $buildargs = $self->associated_metaclass->find_method_by_name("BUILDARGS"); if ( $args eq '@_' and ( !$buildargs or $buildargs->body == \&Moose::Object::BUILDARGS ) ) { # This is the same logic as Moose::Object::BUILDARGS return sprintf( <<'EOF', $self->_inline_throw_error( q{'Single parameters to new() must be a HASH ref'}, 'data => $_[0]' ) ); do { my $params; if ( scalar @_ == 1 ) { unless ( defined $_[0] && ref $_[0] eq 'HASH' ) { %s } $params = { %%{ $_[0] } }; } elsif ( @_ %% 2 ) { Carp::carp( "The new() method for $class expects a hash reference or a key/value list." . " You passed an odd number of arguments" ); $params = { @_, undef }; } else { $params = {@_}; } $params }; EOF ; } else { return $class . "->BUILDARGS($args)"; } } sub _generate_BUILDALL { my $self = shift; my @BUILD_calls; foreach my $method (reverse $self->associated_metaclass->find_all_methods_by_name('BUILD')) { push @BUILD_calls => '$instance->' . $method->{class} . '::BUILD($params)'; } return join ";\n" => @BUILD_calls; } sub _generate_triggers { my $self = shift; my @trigger_calls; foreach my $i ( 0 .. $#{ $self->_attributes } ) { my $attr = $self->_attributes->[$i]; next unless $attr->can('has_trigger') && $attr->has_trigger; my $init_arg = $attr->init_arg; next unless defined $init_arg; push @trigger_calls => '(exists $params->{\'' . $init_arg . '\'}) && do {' . "\n " . '$attrs->[' . $i . ']->trigger->(' . '$instance, ' . $attr->inline_get('$instance') . ', ' . ');' . "\n}"; } return join ";\n" => @trigger_calls; } sub _generate_slot_initializer { my $self = shift; my $index = shift; my $attr = $self->_attributes->[$index]; my @source = ('## ' . $attr->name); my $is_moose = $attr->isa('Moose::Meta::Attribute'); # XXX FIXME if ($is_moose && defined($attr->init_arg) && $attr->is_required && !$attr->has_default && !$attr->has_builder) { push @source => ('(exists $params->{\'' . $attr->init_arg . '\'}) ' . '|| ' . $self->_inline_throw_error('"Attribute (' . quotemeta($attr->name) . ') is required"') .';'); } if (($attr->has_default || $attr->has_builder) && !($is_moose && $attr->is_lazy)) { if ( defined( my $init_arg = $attr->init_arg ) ) { push @source => 'if (exists $params->{\'' . $init_arg . '\'}) {'; push @source => ('my $val = $params->{\'' . $init_arg . '\'};'); push @source => $self->_generate_type_constraint_and_coercion($attr, $index) if $is_moose; push @source => $self->_generate_slot_assignment($attr, '$val', $index); push @source => "} else {"; } my $default; if ( $attr->has_default ) { $default = $self->_generate_default_value($attr, $index); } else { my $builder = $attr->builder; $default = '$instance->' . $builder; } push @source => '{'; # wrap this to avoid my $val overwrite warnings push @source => ('my $val = ' . $default . ';'); push @source => $self->_generate_type_constraint_and_coercion($attr, $index) if $is_moose; push @source => $self->_generate_slot_assignment($attr, '$val', $index); push @source => '}'; # close - wrap this to avoid my $val overrite warnings push @source => "}" if defined $attr->init_arg; } elsif ( defined( my $init_arg = $attr->init_arg ) ) { push @source => '(exists $params->{\'' . $init_arg . '\'}) && do {'; push @source => ('my $val = $params->{\'' . $init_arg . '\'};'); if ($is_moose && $attr->has_type_constraint) { if ($attr->should_coerce && $attr->type_constraint->has_coercion) { push @source => $self->_generate_type_coercion( $attr, '$type_constraints[' . $index . ']', '$val', '$val' ); } push @source => $self->_generate_type_constraint_check( $attr, '$type_constraint_bodies[' . $index . ']', '$type_constraints[' . $index . ']', '$val' ); } push @source => $self->_generate_slot_assignment($attr, '$val', $index); push @source => "}"; } return join "\n" => @source; } sub _generate_slot_assignment { my ($self, $attr, $value, $index) = @_; my $source; if ( $attr->has_initializer ) { return '$attrs->[' . $index . ']->set_initial_value($instance, ' . $value . ');'; } else { return $attr->inline_set( '$instance', $value ) . ';'; } return $source; } sub _generate_type_constraint_and_coercion { my ($self, $attr, $index) = @_; return unless $attr->has_type_constraint; my @source; if ($attr->should_coerce && $attr->type_constraint->has_coercion) { push @source => $self->_generate_type_coercion( $attr, '$type_constraints[' . $index . ']', '$val', '$val' ); } push @source => $self->_generate_type_constraint_check( $attr, ('$type_constraint_bodies[' . $index . ']'), ('$type_constraints[' . $index . ']'), '$val' ); return @source; } sub _generate_type_coercion { my ($self, $attr, $type_constraint_name, $value_name, $return_value_name) = @_; return ($return_value_name . ' = ' . $type_constraint_name . '->coerce(' . $value_name . ');'); } sub _generate_type_constraint_check { my ($self, $attr, $type_constraint_cv, $type_constraint_obj, $value_name) = @_; return ( $self->_inline_throw_error('"Attribute (' # FIXME add 'dad' . quotemeta( $attr->name ) . ') does not pass the type constraint because: " . ' . $type_constraint_obj . '->get_message(' . $value_name . ')') . "\n\t unless " . $type_constraint_cv . '->(' . $value_name . ');' ); } 1; __END__ =pod =head1 NAME Moose::Meta::Method::Constructor - Method Meta Object for constructors =head1 DESCRIPTION This class is a subclass of L<Class::MOP::Method::Constructor> that provides additional Moose-specific functionality To understand this class, you should read the the L<Class::MOP::Method::Constructor> documentation as well. =head1 INHERITANCE C<Moose::Meta::Method::Constructor> is a subclass of L<Moose::Meta::Method> I<and> L<Class::MOP::Method::Constructor>. =head1 BUGS See L<Moose/BUGS> for details on reporting bugs. =head1 AUTHORS Stevan Little E<lt>stevan@iinteractive.comE<gt> =head1 COPYRIGHT AND LICENSE Copyright 2006-2010 by Infinity Interactive, Inc. L<http://www.iinteractive.com> This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. =cut