package Mouse::Meta::Method::Constructor; use Mouse::Util qw(:meta); # enables strict and warnings sub _inline_slot{ my(undef, $self_var, $attr_name) = @_; return sprintf '%s->{q{%s}}', $self_var, $attr_name; } sub _generate_constructor { my ($class, $metaclass, $args) = @_; my $associated_metaclass_name = $metaclass->name; my @attrs = $metaclass->get_all_attributes; my $buildall = $class->_generate_BUILDALL($metaclass); my $buildargs = $class->_generate_BUILDARGS($metaclass); my $processattrs = $class->_generate_processattrs($metaclass, \@attrs); my @checks = map { $_ && $_->_compiled_type_constraint } map { $_->type_constraint } @attrs; my $source = sprintf("#line %d %s\n", __LINE__, __FILE__).<<"..."; sub \{ my \$class = shift; return \$class->Mouse::Object::new(\@_) if \$class ne q{$associated_metaclass_name}; # BUILDARGS $buildargs; my \$instance = bless {}, \$class; # process attributes $processattrs; # BUILDALL $buildall; return \$instance; } ... #warn $source; my $code; my $e = do{ local $@; $code = eval $source; $@; }; die $e if $e; return $code; } sub _generate_processattrs { my ($method_class, $metaclass, $attrs) = @_; my @res; my $has_triggers; my $strict_constructor = $metaclass->__strict_constructor; if($strict_constructor){ push @res, 'my $used = 0;'; } for my $index (0 .. @$attrs - 1) { my $code = ''; my $attr = $attrs->[$index]; my $key = $attr->name; my $init_arg = $attr->init_arg; my $type_constraint = $attr->type_constraint; my $is_weak_ref = $attr->is_weak_ref; my $need_coercion; my $instance_slot = $method_class->_inline_slot('$instance', $key); my $attr_var = "\$attrs[$index]"; my $constraint_var; if(defined $type_constraint){ $constraint_var = "$attr_var\->{type_constraint}"; $need_coercion = ($attr->should_coerce && $type_constraint->has_coercion); } $code .= "# initialize $key\n"; my $post_process = ''; if(defined $type_constraint){ $post_process .= "\$checks[$index]->($instance_slot)"; $post_process .= " or $attr_var->_throw_type_constraint_error($instance_slot, $constraint_var);\n"; } if($is_weak_ref){ $post_process .= "Scalar::Util::weaken($instance_slot) if ref $instance_slot;\n"; } if (defined $init_arg) { my $value = "\$args->{q{$init_arg}}"; $code .= "if (exists $value) {\n"; if($need_coercion){ $value = "$constraint_var->coerce($value)"; } $code .= "$instance_slot = $value;\n"; $code .= $post_process; if ($attr->has_trigger) { $has_triggers++; $code .= "push \@triggers, [$attr_var\->{trigger}, $instance_slot];\n"; } if ($strict_constructor){ $code .= '$used++;' . "\n"; } $code .= "\n} else {\n"; # $value exists } if ($attr->has_default || $attr->has_builder) { unless ($attr->is_lazy) { my $default = $attr->default; my $builder = $attr->builder; my $value; if (defined($builder)) { $value = "\$instance->$builder()"; } elsif (ref($default) eq 'CODE') { $value = "$attr_var\->{default}->(\$instance)"; } elsif (defined($default)) { $value = "$attr_var\->{default}"; } else { $value = 'undef'; } if($need_coercion){ $value = "$constraint_var->coerce($value)"; } $code .= "$instance_slot = $value;\n"; if($is_weak_ref){ $code .= "Scalar::Util::weaken($instance_slot);\n"; } } } elsif ($attr->is_required) { $code .= "Carp::confess('Attribute ($key) is required');"; } $code .= "}\n" if defined $init_arg; push @res, $code; } if($strict_constructor){ push @res, q{if($used < keys %{$args})} . q{{ Mouse::Meta::Method::Constructor::_report_unknown_args($metaclass, \@attrs, $instance, $args) }}; } if($metaclass->is_anon_class){ push @res, q{$instance->{__METACLASS__} = $metaclass;}; } if($has_triggers){ unshift @res, q{my @triggers;}; push @res, q{$_->[0]->($instance, $_->[1]) for @triggers;}; } return join "\n", @res; } sub _generate_BUILDARGS { my(undef, $metaclass) = @_; my $class = $metaclass->name; if ( $class->can('BUILDARGS') && $class->can('BUILDARGS') != \&Mouse::Object::BUILDARGS ) { return 'my $args = $class->BUILDARGS(@_)'; } return <<'...'; my $args; if ( scalar @_ == 1 ) { ( ref( $_[0] ) eq 'HASH' ) || Carp::confess "Single parameters to new() must be a HASH ref"; $args = +{ %{ $_[0] } }; } else { $args = +{@_}; } ... } sub _generate_BUILDALL { my (undef, $metaclass) = @_; return '' unless $metaclass->name->can('BUILD'); my @code; for my $class ($metaclass->linearized_isa) { if (Mouse::Util::get_code_ref($class, 'BUILD')) { unshift @code, qq{${class}::BUILD(\$instance, \$args);}; } } return join "\n", @code; } sub _report_unknown_args { my($metaclass, $attrs, $instance, $args) = @_; my @unknowns; my %init_args; foreach my $attr(@{$attrs}){ my $init_arg = $attr->init_arg; if(defined $init_arg){ $init_args{$init_arg}++; } } while(my $key = each %{$args}){ if(!exists $init_args{$key}){ push @unknowns, $key; } } $metaclass->throw_error( sprintf "Unknown attribute passed to the constructor of %s: %s", ref($instance), join ', ', @unknowns ); } 1; __END__ =head1 NAME Mouse::Meta::Method::Constructor - A Mouse method generator for constructors =head1 VERSION This document describes Mouse version 0.50_01 =head1 SEE ALSO L =cut