2 package Moose::Util::TypeConstraints;
8 use Scalar::Util 'blessed';
10 our $VERSION = '0.05';
12 use Moose::Meta::TypeConstraint;
13 use Moose::Meta::TypeCoercion;
16 require Sub::Exporter;
18 my @exports = qw[type subtype as where message coerce from via find_type_constraint];
20 Sub::Exporter->import(
32 sub find_type_constraint {
33 return $TYPES{$_[0]}->[1]
34 if exists $TYPES{$_[0]};
38 sub _dump_type_constraints {
40 Data::Dumper::Dumper(\%TYPES);
43 sub _create_type_constraint {
44 my ($name, $parent, $check, $message) = @_;
45 my $pkg_defined_in = scalar(caller(1));
46 ($TYPES{$name}->[0] eq $pkg_defined_in)
47 || confess "The type constraint '$name' has already been created "
48 if defined $name && exists $TYPES{$name};
49 $parent = find_type_constraint($parent) if defined $parent;
50 my $constraint = Moose::Meta::TypeConstraint->new(
51 name => $name || '__ANON__',
56 $TYPES{$name} = [ $pkg_defined_in, $constraint ] if defined $name;
60 sub _install_type_coercions {
61 my ($type_name, $coercion_map) = @_;
62 my $type = find_type_constraint($type_name);
63 (!$type->has_coercion)
64 || confess "The type coercion for '$type_name' has already been registered";
65 my $type_coercion = Moose::Meta::TypeCoercion->new(
66 type_coercion_map => $coercion_map,
67 type_constraint => $type
69 $type->coercion($type_coercion);
72 sub export_type_contstraints_as_functions {
75 foreach my $constraint (keys %TYPES) {
76 *{"${pkg}::${constraint}"} = find_type_constraint($constraint)->_compiled_type_constraint;
84 my ($name, $check) = @_;
85 _create_type_constraint($name, undef, $check);
89 unshift @_ => undef if scalar @_ <= 2;
90 _create_type_constraint(@_);
94 my ($type_name, @coercion_map) = @_;
95 _install_type_coercions($type_name, \@coercion_map);
99 sub from ($) { $_[0] }
100 sub where (&) { $_[0] }
101 sub via (&) { $_[0] }
102 sub message (&) { $_[0] }
104 # define some basic types
106 type 'Any' => where { 1 }; # meta-type including all
107 type 'Item' => where { 1 }; # base-type
109 subtype 'Undef' => as 'Item' => where { !defined($_) };
110 subtype 'Defined' => as 'Item' => where { defined($_) };
112 subtype 'Value' => as 'Item' => where { !ref($_) };
113 subtype 'Ref' => as 'Item' => where { ref($_) };
115 subtype 'Bool' => as 'Item' => where { !defined($_) || $_ eq "" || "$_" eq '1' || "$_" eq '0' };
117 subtype 'Str' => as 'Value' => where { defined($_) };
119 subtype 'Num' => as 'Value' => where { Scalar::Util::looks_like_number($_) };
120 subtype 'Int' => as 'Num' => where { "$_" =~ /^[0-9]+$/ };
122 subtype 'ScalarRef' => as 'Ref' => where { ref($_) eq 'SCALAR' };
124 subtype 'CollectionRef' => as 'Ref' => where { ref($_) eq 'ARRAY' || ref($_) eq 'HASH' };
126 subtype 'ArrayRef' => as 'CollectionRef' => where { ref($_) eq 'ARRAY' };
127 subtype 'HashRef' => as 'CollectionRef' => where { ref($_) eq 'HASH' };
129 subtype 'CodeRef' => as 'Ref' => where { ref($_) eq 'CODE' };
130 subtype 'RegexpRef' => as 'Ref' => where { ref($_) eq 'Regexp' };
133 # blessed(qr/.../) returns true,.. how odd
134 subtype 'Object' => as 'Ref' => where { blessed($_) && blessed($_) ne 'Regexp' };
136 subtype 'Role' => as 'Object' => where { $_->can('does') };
146 Moose::Util::TypeConstraints - Type constraint system for Moose
150 use Moose::Util::TypeConstraints;
152 type Num => where { Scalar::Util::looks_like_number($_) };
158 subtype NaturalLessThanTen
161 => message { "This number ($_) is not less than ten!" };
169 This module provides Moose with the ability to create type contraints
170 to be are used in both attribute definitions and for method argument
173 =head2 Important Caveat
175 This is B<NOT> a type system for Perl 5. These are type constraints,
176 and they are not used by Moose unless you tell it to. No type
177 inference is performed, expression are not typed, etc. etc. etc.
179 This is simply a means of creating small constraint functions which
180 can be used to simplify your own type-checking code.
182 =head2 Default Type Constraints
184 This module also provides a simple hierarchy for Perl 5 types, this
185 could probably use some work, but it works for me at the moment.
206 Suggestions for improvement are welcome.
210 =head2 Type Constraint Registry
214 =item B<find_type_constraint ($type_name)>
216 This function can be used to locate a specific type constraint
217 meta-object. What you do with it from there is up to you :)
219 =item B<export_type_contstraints_as_functions>
221 This will export all the current type constraints as functions
222 into the caller's namespace. Right now, this is mostly used for
223 testing, but it might prove useful to others.
227 =head2 Type Constraint Constructors
229 The following functions are used to create type constraints.
230 They will then register the type constraints in a global store
231 where Moose can get to them if it needs to.
233 See the L<SYNOPOSIS> for an example of how to use these.
237 =item B<type ($name, $where_clause)>
239 This creates a base type, which has no parent.
241 =item B<subtype ($name, $parent, $where_clause, ?$message)>
243 This creates a named subtype.
245 =item B<subtype ($parent, $where_clause, ?$message)>
247 This creates an unnamed subtype and will return the type
248 constraint meta-object, which will be an instance of
249 L<Moose::Meta::TypeConstraint>.
253 This is just sugar for the type constraint construction syntax.
257 This is just sugar for the type constraint construction syntax.
261 This is just sugar for the type constraint construction syntax.
265 =head2 Type Coercion Constructors
267 Type constraints can also contain type coercions as well. In most
268 cases Moose will run the type-coercion code first, followed by the
269 type constraint check. This feature should be used carefully as it
270 is very powerful and could easily take off a limb if you are not
273 See the L<SYNOPOSIS> for an example of how to use these.
281 This is just sugar for the type coercion construction syntax.
285 This is just sugar for the type coercion construction syntax.
291 All complex software has bugs lurking in it, and this module is no
292 exception. If you find a bug please either email me, or add the bug
297 Stevan Little E<lt>stevan@iinteractive.comE<gt>
299 =head1 COPYRIGHT AND LICENSE
301 Copyright 2006 by Infinity Interactive, Inc.
303 L<http://www.iinteractive.com>
305 This library is free software; you can redistribute it and/or modify
306 it under the same terms as Perl itself.