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;
}
...
my $code;
my $e = do{
local $@;
$code = eval $source;
$@;
};
die $e if $e;
return $code;
}
sub _generate_processattrs {
my ($class, $metaclass, $attrs) = @_;
my @res;
my $has_triggers;
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 $need_coercion;
my $instance_slot = "\$instance->{q{$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 $attr_var->verify_type_constraint_error(q{$key}, $instance_slot, $constraint_var);\n";
}
if($attr->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";
}
$code .= "\n} else {\n";
}
if ($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 = $value;\n";
}
}
elsif ($attr->is_required) {
$code .= "Carp::confess('Attribute ($key) is required');";
}
$code .= "}\n" if defined $init_arg;
push @res, $code;
}
if($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) {
no strict 'refs';
no warnings 'once';
if (*{ $class . '::BUILD' }{CODE}) {
unshift @code, qq{${class}::BUILD(\$instance, \$args);};
}
}
return join "\n", @code;
}
1;