package MooseX::Types::TypeDecorator;
use strict;
use warnings;
use Carp::Clan qw( ^MooseX::Types );
use Moose::Util::TypeConstraints ();
use Moose::Meta::TypeConstraint::Union;
use Scalar::Util qw(blessed);
use overload(
'""' => sub {
my $self = shift @_;
if(blessed $self) {
return $self->__type_constraint->name;
} else {
return "$self";
}
},
'|' => sub {
## It's kind of ugly that we need to know about Union Types, but this
## is needed for syntax compatibility. Maybe someday we'll all just do
## Or[Str,Str,Int]
my @args = @_[0,1]; ## arg 3 is special, see the overload docs.
my @tc = grep {blessed $_} map {
blessed $_ ? $_ :
Moose::Util::TypeConstraints::find_or_parse_type_constraint($_)
|| __PACKAGE__->_throw_error( "$_ is not a type constraint")
} @args;
( scalar @tc == scalar @args)
|| __PACKAGE__->_throw_error(
"one of your type constraints is bad. Passed: ". join(', ', @args) ." Got: ". join(', ', @tc));
( scalar @tc >= 2 )
|| __PACKAGE__->_throw_error("You must pass in at least 2 type names to make a union");
my $union = Moose::Meta::TypeConstraint::Union->new(type_constraints=>\@tc);
return Moose::Util::TypeConstraints::register_type_constraint($union);
},
fallback => 1,
);
=head1 NAME
MooseX::Types::TypeDecorator - More flexible access to a Type Constraint
=head1 DESCRIPTION
This is a decorator object that contains an underlying type constraint. We use
this to control access to the type constraint and to add some features.
=head1 METHODS
This class defines the following methods.
=head2 new
Old school instantiation
=cut
sub new {
my $class = shift @_;
if(my $arg = shift @_) {
if(blessed $arg && $arg->isa('Moose::Meta::TypeConstraint')) {
return bless {'__type_constraint'=>$arg}, $class;
} elsif(
blessed $arg &&
$arg->isa('MooseX::Types::UndefinedType')
) {
## stub in case we'll need to handle these types differently
return bless {'__type_constraint'=>$arg}, $class;
} elsif(blessed $arg) {
__PACKAGE__->_throw_error("Argument must be ->isa('Moose::Meta::TypeConstraint') or ->isa('MooseX::Types::UndefinedType'), not ". blessed $arg);
} else {
__PACKAGE__->_throw_error("Argument cannot be '$arg'");
}
} else {
__PACKAGE__->_throw_error("This method [new] requires a single argument.");
}
}
=head2 __type_constraint ($type_constraint)
Set/Get the type_constraint.
=cut
sub __type_constraint {
my $self = shift @_;
if(blessed $self) {
if(defined(my $tc = shift @_)) {
$self->{__type_constraint} = $tc;
}
return $self->{__type_constraint};
} else {
__PACKAGE__->_throw_error('cannot call __type_constraint as a class method');
}
}
=head2 isa
handle $self->isa since AUTOLOAD can't.
=cut
sub isa {
my ($self, $target) = @_;
if(defined $target) {
if(blessed $self) {
return $self->__type_constraint->isa($target);
} else {
return;
}
} else {
return;
}
}
=head2 can
handle $self->can since AUTOLOAD can't.
=cut
sub can {
my ($self, $target) = @_;
if(defined $target) {
if(blessed $self) {
return $self->__type_constraint->can($target);
} else {
return;
}
} else {
return;
}
}
=head2 meta
have meta examine the underlying type constraints
=cut
sub meta {
my $self = shift @_;
if(blessed $self) {
return $self->__type_constraint->meta;
}
}
=head2 _throw_error
properly delegate error messages
=cut
sub _throw_error {
shift;
require Moose;
unshift @_, 'Moose';
goto &Moose::throw_error;
}
=head2 DESTROY
We might need it later
=cut
sub DESTROY {
return;
}
=head2 AUTOLOAD
Delegate to the decorator targe
=cut
sub AUTOLOAD {
my ($self, @args) = @_;
my ($method) = (our $AUTOLOAD =~ /([^:]+)$/);
## We delegate with this method in an attempt to support a value of
## __type_constraint which is also AUTOLOADing, in particular the class
## MooseX::Types::UndefinedType which AUTOLOADs during autovivication.
my $return;
eval {
$return = $self->__type_constraint->$method(@args);
}; if($@) {
__PACKAGE__->_throw_error($@);
} else {
return $return;
}
}
=head1 AUTHOR AND COPYRIGHT
John Napiorkowski (jnapiorkowski) <jjnapiork@cpan.org>
=head1 LICENSE
This program is free software; you can redistribute it and/or modify
it under the same terms as perl itself.
=cut
1;