package Moose::Meta::Method::Constructor;
use strict;
use warnings;
use Scalar::Util 'blessed', 'weaken', 'looks_like_number', 'refaddr';
our $VERSION = '1.00';
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" . 'return $class->Moose::Object::new(@_)';
$source .= "\n if \$class ne '" . $self->associated_metaclass->name
. "';\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 ( $code, $e ) = $self->_compile_code(
code => $source,
environment => {
'$meta' => \$self,
'$attrs' => \$attrs,
'@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_params {
my ( $self, $var, $class_var ) = @_;
"my $var = " . $self->_generate_BUILDARGS( $class_var, '@_' ) . ";\n";
}
sub _generate_instance {
my ( $self, $var, $class_var ) = @_;
"my $var = "
. $self->_meta_instance->inline_create_instance($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 ) ) {
return join("\n",
'do {',
$self->_inline_throw_error('"Single parameters to new() must be a HASH ref"', 'data => $_[0]'),
' if scalar @_ == 1 && !( defined $_[0] && ref $_[0] eq q{HASH} );',
'(scalar @_ == 1) ? {%{$_[0]}} : {@_};',
'}',
);
} 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, '
. $self->_meta_instance->inline_get_slot_value(
'$instance',
$attr->name,
)
. ', '
. ');' . "\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) {
$source = (
'$attrs->[' . $index . ']->set_initial_value($instance, ' . $value . ');'
);
}
else {
$source = (
$self->_meta_instance->inline_set_slot_value(
'$instance',
$attr->name,
$value
) . ';'
);
}
my $is_moose = $attr->isa('Moose::Meta::Attribute'); # XXX FIXME
if ($is_moose && $attr->is_weak_ref) {
$source .= (
"\n" .
$self->_meta_instance->inline_weaken_slot_value(
'$instance',
$attr->name
) .
' if ref ' . $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 . '->(' . $value_name . ');'
);
}
sub _generate_default_value {
my ($self, $attr, $index) = @_;
# NOTE:
# default values can either be CODE refs
# in which case we need to call them. Or
# they can be scalars (strings/numbers)
# in which case we can just deal with them
# in the code we eval.
if ($attr->is_default_a_coderef) {
return '$attrs->[' . $index . ']->default($instance)';
}
else {
return q{"} . quotemeta( $attr->default ) . q{"};
}
}
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