1 package Mouse::Meta::Method::Constructor;
2 use Mouse::Util qw(:meta); # enables strict and warnings
4 sub _inline_create_instance {
5 my(undef, $class_expr) = @_;
6 return "bless {}, $class_expr";
10 my(undef, $self_var, $attr_name) = @_;
11 return sprintf '%s->{q{%s}}', $self_var, $attr_name;
14 sub _inline_has_slot {
15 my($class, $self_var, $attr_name) = @_;
17 return sprintf 'exists(%s)', $class->_inline_slot($self_var, $attr_name);
20 sub _inline_get_slot {
21 my($class, $self_var, $attr_name) = @_;
23 return $class->_inline_slot($self_var, $attr_name);
26 sub _inline_set_slot {
27 my($class, $self_var, $attr_name, $rvalue) = @_;
29 return $class->_inline_slot($self_var, $attr_name) . " = $rvalue";
32 sub _inline_weaken_slot {
33 my($class, $self_var, $attr_name) = @_;
35 return sprintf 'Scalar::Util::weaken(%s)', $class->_inline_slot($self_var, $attr_name);
38 sub _generate_constructor {
39 my ($class, $metaclass, $args) = @_;
41 my @attrs = $metaclass->get_all_attributes;
43 my $init_attrs = $class->_generate_processattrs($metaclass, \@attrs);
44 my $buildargs = $class->_generate_BUILDARGS($metaclass);
45 my $buildall = $class->_generate_BUILDALL($metaclass);
47 my @checks = map { $_ && $_->_compiled_type_constraint }
48 map { $_->type_constraint } @attrs;
50 my $class_name = $metaclass->name;
51 my $source = sprintf(<<'END_CONSTRUCTOR', $class_name, __LINE__, __FILE__, $class_name, $buildargs, $class->_inline_create_instance('$class'), $init_attrs, $buildall);
53 #line %d "constructor of %s (%s)"
56 return $class->Mouse::Object::new(@_)
57 if $class ne __PACKAGE__;
80 sub _generate_processattrs {
81 my ($method_class, $metaclass, $attrs) = @_;
85 my $strict = $metaclass->__strict_constructor;
88 push @res, 'my $used = 0;';
91 for my $index (0 .. @$attrs - 1) {
94 my $attr = $attrs->[$index];
95 my $key = $attr->name;
97 my $init_arg = $attr->init_arg;
98 my $type_constraint = $attr->type_constraint;
99 my $is_weak_ref = $attr->is_weak_ref;
102 my $instance = '$instance';
103 my $instance_slot = $method_class->_inline_get_slot($instance, $key);
104 my $attr_var = "\$attrs[$index]";
107 if(defined $type_constraint){
108 $constraint_var = "$attr_var\->{type_constraint}";
109 $need_coercion = ($attr->should_coerce && $type_constraint->has_coercion);
112 $code .= "# initialize $key\n";
114 my $post_process = '';
115 if(defined $type_constraint){
116 $post_process .= "\$checks[$index]->($instance_slot)";
117 $post_process .= " or $attr_var->_throw_type_constraint_error($instance_slot, $constraint_var);\n";
120 $post_process .= $method_class->_inline_weaken_slot($instance, $key) . " if ref $instance_slot;\n";
123 if (defined $init_arg) {
124 my $value = "\$args->{q{$init_arg}}";
126 $code .= "if (exists $value) {\n";
129 $value = "$constraint_var->coerce($value)";
132 $code .= $method_class->_inline_set_slot($instance, $key, $value) . ";\n";
133 $code .= $post_process;
135 if ($attr->has_trigger) {
137 $code .= "push \@triggers, [$attr_var\->{trigger}, $instance_slot];\n";
141 $code .= '++$used;' . "\n";
144 $code .= "\n} else {\n"; # $value exists
147 if ($attr->has_default || $attr->has_builder) {
148 unless ($attr->is_lazy) {
149 my $default = $attr->default;
150 my $builder = $attr->builder;
153 if (defined($builder)) {
154 $value = "\$instance->$builder()";
156 elsif (ref($default) eq 'CODE') {
157 $value = "$attr_var\->{default}->(\$instance)";
159 elsif (defined($default)) {
160 $value = "$attr_var\->{default}";
167 $value = "$constraint_var->coerce($value)";
170 $code .= $method_class->_inline_set_slot($instance, $key, $value) . ";\n";
172 $code .= $method_class->_inline_weaken_slot($instance, $key) . ";\n";
176 elsif ($attr->is_required) {
177 $code .= "Carp::confess('Attribute ($key) is required');";
180 $code .= "}\n" if defined $init_arg;
186 push @res, q{if($used < keys %{$args})}
187 . sprintf q{{ %s->_report_unknown_args($metaclass, \@attrs, $args) }}, $method_class;
190 if($metaclass->is_anon_class){
191 push @res, q{$instance->{__METACLASS__} = $metaclass;};
195 unshift @res, q{my @triggers;};
196 push @res, q{$_->[0]->($instance, $_->[1]) for @triggers;};
199 return join "\n", @res;
202 sub _generate_BUILDARGS {
203 my(undef, $metaclass) = @_;
205 my $class = $metaclass->name;
206 if ( $class->can('BUILDARGS') && $class->can('BUILDARGS') != \&Mouse::Object::BUILDARGS ) {
207 return 'my $args = $class->BUILDARGS(@_)';
212 if ( scalar @_ == 1 ) {
213 ( ref( $_[0] ) eq 'HASH' )
214 || Carp::confess "Single parameters to new() must be a HASH ref";
215 $args = +{ %{ $_[0] } };
223 sub _generate_BUILDALL {
224 my (undef, $metaclass) = @_;
226 return '' unless $metaclass->name->can('BUILD');
229 for my $class ($metaclass->linearized_isa) {
230 if (Mouse::Util::get_code_ref($class, 'BUILD')) {
231 unshift @code, qq{${class}::BUILD(\$instance, \$args);};
234 return join "\n", @code;
237 sub _report_unknown_args {
238 my(undef, $metaclass, $attrs, $args) = @_;
242 foreach my $attr(@{$attrs}){
243 my $init_arg = $attr->init_arg;
244 if(defined $init_arg){
245 $init_args{$init_arg}++;
249 while(my $key = each %{$args}){
250 if(!exists $init_args{$key}){
251 push @unknowns, $key;
255 $metaclass->throw_error( sprintf
256 "Unknown attribute passed to the constructor of %s: %s",
257 $metaclass->name, Mouse::Util::english_list(@unknowns),
266 Mouse::Meta::Method::Constructor - A Mouse method generator for constructors
270 This document describes Mouse version 0.50_04
274 L<Moose::Meta::Method::Constructor>