1 package MooseX::Types::Structured;
4 use Moose::Util::TypeConstraints;
5 use MooseX::Meta::TypeConstraint::Structured::Positional;
6 use MooseX::Meta::TypeConstraint::Structured::Named;
7 #use MooseX::Types::Moose qw();
8 #use MooseX::Types -declare => [qw( Dict Tuple Optional )];
10 -setup => { exports => [ qw(Dict Tuple Optional) ] };
12 our $VERSION = '0.01';
13 our $AUTHORITY = 'cpan:JJNAPIORK';
17 MooseX::Types::Structured; Structured Type Constraints for Moose
21 The following is example usage for this module. You can define a class that has
22 an attribute with a structured type like so:
24 package MyApp::MyClass;
27 use MooseX::Types::Moose qw(Str Int);
28 use MooseX::Types::Structured qw(Dict Tuple);
30 has name => (isa=>Dict[first_name=>Str, last_name=>Str]);
32 Then you can instantiate this class with something like:
34 my $instance = MyApp::MyClass->new(
35 name=>{first_name=>'John', last_name=>'Napiorkowski'},
38 But all of these would cause an error:
40 my $instance = MyApp::MyClass->new(name=>'John');
41 my $instance = MyApp::MyClass->new(name=>{first_name=>'John'});
42 my $instance = MyApp::MyClass->new(name=>{first_name=>'John', age=>39});
44 Please see the test cases for more examples.
48 This type library enables structured type constraints. Basically, this is very
49 similar to parameterized constraints that are built into the core Moose types,
50 except that you are allowed to define the container's entire structure. For
51 example, you could define a parameterized constraint like so:
53 subtype HashOfInts, as Hashref[Int];
55 which would constraint a value to something like [1,2,3,...] and so one. A
56 structured constraint like so:
58 subtype StringFollowedByInt, as Tuple[Str,Int];
60 would constrain it's value to something like ['hello', 111];
62 These structures can be as simple or elaborate as you wish. You can even
63 combine various structured, parameterized and simple constraints all together:
65 subtype crazy, as Tuple[Int, Dict[name=>Str, age=>Int], ArrayRef[Int]];
67 Which would match "[1, {name=>'John', age=>25},[10,11,12]]".
69 You should exercise some care as to whether or not your complex structured
70 constraints would be better off contained by a real object as in the following
74 package MyApp::MyStruct;
77 has $_ for qw(name age);
79 package MyApp::MyClass;
82 has person => (isa=>'MyApp::MyStruct');
85 my $instance = MyApp::MyClass
86 ->new( person=>MyApp::MyStruct->new(name=>'John', age=>39) );
88 This method may take some additional time to setup but will give you more
89 flexibility. However, structured constraints are highly compatible with this
90 method, granting some interesting possibilities for coercion. Try:
96 from (Dict[name=>Str, age=>Int]),
98 MyApp::MyStruct->new(%$_);
100 from (Dict[last_name=>Str, first_name=>Str, dob=>DateTime]),
102 my $name = _->{first_name} .' '. $_->{last_name};
103 my $age = $_->{dob} - DateTime->now;
104 MyApp::MyStruct->new(
112 This class defines the following types and subtypes.
117 return bless {args=>shift}, 'MooseX::Types::Optional';
121 my ($args, $optional) = _normalize_args(@_);
123 my @optional = ref $optional eq 'ARRAY' ? @$optional : ();
125 return MooseX::Meta::TypeConstraint::Structured::Positional->new(
127 parent => find_type_constraint('ArrayRef'),
128 package_defined_in => __PACKAGE__,
130 _normalize_type_constraint($_);
132 optional_signature => [map {
133 _normalize_type_constraint($_);
139 my ($args, $optional) = _normalize_args(@_);
141 my %optional = ref $optional eq 'ARRAY' ? @$optional : ();
143 return MooseX::Meta::TypeConstraint::Structured::Named->new(
145 parent => find_type_constraint('HashRef'),
146 package_defined_in => __PACKAGE__,
148 $_ => _normalize_type_constraint($args{$_});
150 optional_signature => {map {
151 $_ => _normalize_type_constraint($optional{$_});
156 sub _normalize_args {
158 confess "Structured Type Constraints can only accept an ArrayRef as arguments"
159 unless ref $args eq 'ARRAY';
162 my $last = pop @args;
164 if(blessed $last && $last->isa('MooseX::Types::Optional')) {
165 return ([@args], $last->{args});
167 return ([@args, $last]);
171 sub _normalize_type_constraint {
174 ## If incoming is an object, we will assume it's something that implements
175 ## what a type constraint is. We should probably have a Role for this...
176 if(defined $tc && blessed $tc) {
179 return Moose::Util::TypeConstraints::find_or_parse_type_constraint($tc);
185 The following modules or resources may be of interest.
187 L<Moose>, L<MooseX::TypeLibrary>, L<Moose::Meta::TypeConstraint>
191 No known or reported bugs.
195 John Napiorkowski, C<< <jjnapiork@cpan.org> >>
197 =head1 COPYRIGHT & LICENSE
199 This program is free software; you can redistribute it and/or modify
200 it under the same terms as Perl itself.