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($_) };
112 subtype 'Bool' => as 'Item' => where { !defined($_) || $_ eq "" || "$_" eq '1' || "$_" eq '0' };
114 subtype 'Value' => as 'Defined' => where { !ref($_) };
115 subtype 'Ref' => as 'Defined' => where { ref($_) };
117 subtype 'Str' => as 'Value' => where { 1 };
119 subtype 'Num' => as 'Value' => where { Scalar::Util::looks_like_number($_) };
120 subtype 'Int' => as 'Num' => where { "$_" =~ /^[0-9]+$/ };
122 subtype 'ScalarRef' => as 'Ref' => where { ref($_) eq 'SCALAR' };
123 subtype 'ArrayRef' => as 'Ref' => where { ref($_) eq 'ARRAY' };
124 subtype 'HashRef' => as 'Ref' => where { ref($_) eq 'HASH' };
125 subtype 'CodeRef' => as 'Ref' => where { ref($_) eq 'CODE' };
126 subtype 'RegexpRef' => as 'Ref' => where { ref($_) eq 'Regexp' };
129 # blessed(qr/.../) returns true,.. how odd
130 subtype 'Object' => as 'Ref' => where { blessed($_) && blessed($_) ne 'Regexp' };
132 subtype 'Role' => as 'Object' => where { $_->can('does') };
142 Moose::Util::TypeConstraints - Type constraint system for Moose
146 use Moose::Util::TypeConstraints;
148 type Num => where { Scalar::Util::looks_like_number($_) };
154 subtype NaturalLessThanTen
157 => message { "This number ($_) is not less than ten!" };
165 This module provides Moose with the ability to create type contraints
166 to be are used in both attribute definitions and for method argument
169 =head2 Important Caveat
171 This is B<NOT> a type system for Perl 5. These are type constraints,
172 and they are not used by Moose unless you tell it to. No type
173 inference is performed, expression are not typed, etc. etc. etc.
175 This is simply a means of creating small constraint functions which
176 can be used to simplify your own type-checking code.
178 =head2 Default Type Constraints
180 This module also provides a simple hierarchy for Perl 5 types, this
181 could probably use some work, but it works for me at the moment.
201 Suggestions for improvement are welcome.
205 =head2 Type Constraint Registry
209 =item B<find_type_constraint ($type_name)>
211 This function can be used to locate a specific type constraint
212 meta-object. What you do with it from there is up to you :)
214 =item B<export_type_contstraints_as_functions>
216 This will export all the current type constraints as functions
217 into the caller's namespace. Right now, this is mostly used for
218 testing, but it might prove useful to others.
222 =head2 Type Constraint Constructors
224 The following functions are used to create type constraints.
225 They will then register the type constraints in a global store
226 where Moose can get to them if it needs to.
228 See the L<SYNOPOSIS> for an example of how to use these.
232 =item B<type ($name, $where_clause)>
234 This creates a base type, which has no parent.
236 =item B<subtype ($name, $parent, $where_clause, ?$message)>
238 This creates a named subtype.
240 =item B<subtype ($parent, $where_clause, ?$message)>
242 This creates an unnamed subtype and will return the type
243 constraint meta-object, which will be an instance of
244 L<Moose::Meta::TypeConstraint>.
248 This is just sugar for the type constraint construction syntax.
252 This is just sugar for the type constraint construction syntax.
256 This is just sugar for the type constraint construction syntax.
260 =head2 Type Coercion Constructors
262 Type constraints can also contain type coercions as well. In most
263 cases Moose will run the type-coercion code first, followed by the
264 type constraint check. This feature should be used carefully as it
265 is very powerful and could easily take off a limb if you are not
268 See the L<SYNOPOSIS> for an example of how to use these.
276 This is just sugar for the type coercion construction syntax.
280 This is just sugar for the type coercion construction syntax.
286 All complex software has bugs lurking in it, and this module is no
287 exception. If you find a bug please either email me, or add the bug
292 Stevan Little E<lt>stevan@iinteractive.comE<gt>
294 =head1 COPYRIGHT AND LICENSE
296 Copyright 2006 by Infinity Interactive, Inc.
298 L<http://www.iinteractive.com>
300 This library is free software; you can redistribute it and/or modify
301 it under the same terms as Perl itself.