2 package Moose::Util::TypeConstraints;
8 use List::MoreUtils qw( all );
9 use Scalar::Util 'blessed';
12 our $VERSION = '0.59';
13 $VERSION = eval $VERSION;
14 our $AUTHORITY = 'cpan:STEVAN';
16 ## --------------------------------------------------------
17 # Prototyped subs must be predeclared because we have a
18 # circular dependency with Moose::Meta::Attribute et. al.
19 # so in case of us being use'd first the predeclaration
20 # ensures the prototypes are in scope when consumers are
30 sub _create_type_constraint ($$$;$$);
31 sub _install_type_coercions ($$);
33 ## --------------------------------------------------------
35 use Moose::Meta::TypeConstraint;
36 use Moose::Meta::TypeConstraint::Union;
37 use Moose::Meta::TypeConstraint::Parameterized;
38 use Moose::Meta::TypeConstraint::Parameterizable;
39 use Moose::Meta::TypeConstraint::Class;
40 use Moose::Meta::TypeConstraint::Role;
41 use Moose::Meta::TypeConstraint::Enum;
42 use Moose::Meta::TypeCoercion;
43 use Moose::Meta::TypeCoercion::Union;
44 use Moose::Meta::TypeConstraint::Registry;
45 use Moose::Util::TypeConstraints::OptimizedConstraints;
47 Moose::Exporter->setup_import_methods(
50 type subtype class_type role_type as where message optimize_as
54 register_type_constraint )
59 ## --------------------------------------------------------
60 ## type registry and some useful functions for it
61 ## --------------------------------------------------------
63 my $REGISTRY = Moose::Meta::TypeConstraint::Registry->new;
65 sub get_type_constraint_registry { $REGISTRY }
66 sub list_all_type_constraints { keys %{$REGISTRY->type_constraints} }
67 sub export_type_constraints_as_functions {
70 foreach my $constraint (keys %{$REGISTRY->type_constraints}) {
71 my $tc = $REGISTRY->get_type_constraint($constraint)->_compiled_type_constraint;
72 *{"${pkg}::${constraint}"} = sub { $tc->($_[0]) ? 1 : undef }; # the undef is for compat
76 sub create_type_constraint_union {
77 my @type_constraint_names;
79 if (scalar @_ == 1 && _detect_type_constraint_union($_[0])) {
80 @type_constraint_names = _parse_type_constraint_union($_[0]);
83 @type_constraint_names = @_;
86 (scalar @type_constraint_names >= 2)
87 || Moose->throw_error("You must pass in at least 2 type names to make a union");
89 my @type_constraints = map {
90 find_or_parse_type_constraint($_) ||
91 Moose->throw_error("Could not locate type constraint ($_) for the union");
92 } @type_constraint_names;
94 return Moose::Meta::TypeConstraint::Union->new(
95 type_constraints => \@type_constraints
99 sub create_parameterized_type_constraint {
100 my $type_constraint_name = shift;
101 my ($base_type, $type_parameter) = _parse_parameterized_type_constraint($type_constraint_name);
103 (defined $base_type && defined $type_parameter)
104 || Moose->throw_error("Could not parse type name ($type_constraint_name) correctly");
106 if ($REGISTRY->has_type_constraint($base_type)) {
107 my $base_type_tc = $REGISTRY->get_type_constraint($base_type);
108 return _create_parameterized_type_constraint(
113 Moose->throw_error("Could not locate the base type ($base_type)");
117 sub _create_parameterized_type_constraint {
118 my ( $base_type_tc, $type_parameter ) = @_;
119 if ( $base_type_tc->can('parameterize') ) {
120 return $base_type_tc->parameterize($type_parameter);
122 return Moose::Meta::TypeConstraint::Parameterized->new(
123 name => $base_type_tc->name . '[' . $type_parameter . ']',
124 parent => $base_type_tc,
125 type_parameter => find_or_create_isa_type_constraint($type_parameter),
130 #should we also support optimized checks?
131 sub create_class_type_constraint {
132 my ( $class, $options ) = @_;
134 # too early for this check
135 #find_type_constraint("ClassName")->check($class)
136 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
144 $options{name} ||= "__ANON__";
146 Moose::Meta::TypeConstraint::Class->new( %options );
149 sub create_role_type_constraint {
150 my ( $role, $options ) = @_;
152 # too early for this check
153 #find_type_constraint("ClassName")->check($class)
154 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
162 $options{name} ||= "__ANON__";
164 Moose::Meta::TypeConstraint::Role->new( %options );
168 sub find_or_create_type_constraint {
169 my ( $type_constraint_name, $options_for_anon_type ) = @_;
171 if ( my $constraint = find_or_parse_type_constraint($type_constraint_name) ) {
174 elsif ( defined $options_for_anon_type ) {
176 # if there is no $options_for_anon_type
177 # specified, then we assume they don't
178 # want to create one, and return nothing.
180 # otherwise assume that we should create
181 # an ANON type with the $options_for_anon_type
182 # options which can be passed in. It should
183 # be noted that these don't get registered
184 # so we need to return it.
186 return Moose::Meta::TypeConstraint->new(
188 %{$options_for_anon_type}
195 sub find_or_create_isa_type_constraint {
196 my $type_constraint_name = shift;
197 find_or_parse_type_constraint($type_constraint_name) || create_class_type_constraint($type_constraint_name)
200 sub find_or_create_does_type_constraint {
201 my $type_constraint_name = shift;
202 find_or_parse_type_constraint($type_constraint_name) || create_role_type_constraint($type_constraint_name)
205 sub find_or_parse_type_constraint {
206 my $type_constraint_name = normalize_type_constraint_name(shift);
209 if ($constraint = find_type_constraint($type_constraint_name)) {
211 } elsif (_detect_type_constraint_union($type_constraint_name)) {
212 $constraint = create_type_constraint_union($type_constraint_name);
213 } elsif (_detect_parameterized_type_constraint($type_constraint_name)) {
214 $constraint = create_parameterized_type_constraint($type_constraint_name);
219 $REGISTRY->add_type_constraint($constraint);
223 sub normalize_type_constraint_name {
224 my $type_constraint_name = shift;
225 $type_constraint_name =~ s/\s//g;
226 return $type_constraint_name;
232 local $Carp::CarpLevel = $Carp::CarpLevel + 1;
233 Carp::confess($error);
236 ## --------------------------------------------------------
237 ## exported functions ...
238 ## --------------------------------------------------------
240 sub find_type_constraint {
243 if ( blessed $type and $type->isa("Moose::Meta::TypeConstraint") ) {
247 return unless $REGISTRY->has_type_constraint($type);
248 return $REGISTRY->get_type_constraint($type);
252 sub register_type_constraint {
253 my $constraint = shift;
254 Moose->throw_error("can't register an unnamed type constraint") unless defined $constraint->name;
255 $REGISTRY->add_type_constraint($constraint);
262 splice(@_, 1, 0, undef);
263 goto &_create_type_constraint;
268 # this adds an undef for the name
269 # if this is an anon-subtype:
270 # subtype(Num => where { $_ % 2 == 0 }) # anon 'even' subtype
272 # subtype(Num => where { $_ % 2 == 0 }) message { "$_ must be an even number" }
274 # but if the last arg is not a code ref then it is a subtype
277 # subtype(MyNumbers => as Num); # now MyNumbers is the same as Num
278 # ... yeah I know it's ugly code
280 unshift @_ => undef if scalar @_ == 2 && ( 'CODE' eq ref( $_[-1] ) );
282 if scalar @_ == 3 && all { ref($_) =~ /^(?:CODE|HASH)$/ } @_[ 1, 2 ];
283 goto &_create_type_constraint;
287 register_type_constraint(
288 create_class_type_constraint(
290 ( defined($_[1]) ? $_[1] : () ),
295 sub role_type ($;$) {
296 register_type_constraint(
297 create_role_type_constraint(
299 ( defined($_[1]) ? $_[1] : () ),
305 my ($type_name, @coercion_map) = @_;
306 _install_type_coercions($type_name, \@coercion_map);
311 sub where (&) { $_[0] }
312 sub via (&) { $_[0] }
314 sub message (&) { +{ message => $_[0] } }
315 sub optimize_as (&) { +{ optimized => $_[0] } }
318 my ($type_name, @values) = @_;
320 # if only an array-ref is passed then
321 # you get an anon-enum
323 if (ref $type_name eq 'ARRAY' && !@values) {
324 @values = @$type_name;
327 (scalar @values >= 2)
328 || Moose->throw_error("You must have at least two values to enumerate through");
329 my %valid = map { $_ => 1 } @values;
331 register_type_constraint(
332 create_enum_type_constraint(
339 sub create_enum_type_constraint {
340 my ( $type_name, $values ) = @_;
342 Moose::Meta::TypeConstraint::Enum->new(
343 name => $type_name || '__ANON__',
348 ## --------------------------------------------------------
349 ## desugaring functions ...
350 ## --------------------------------------------------------
352 sub _create_type_constraint ($$$;$$) {
357 my ($message, $optimized);
359 $message = $_->{message} if exists $_->{message};
360 $optimized = $_->{optimized} if exists $_->{optimized};
363 my $pkg_defined_in = scalar(caller(0));
366 my $type = $REGISTRY->get_type_constraint($name);
368 ( $type->_package_defined_in eq $pkg_defined_in )
370 "The type constraint '$name' has already been created in "
371 . $type->_package_defined_in
372 . " and cannot be created again in "
377 ## Here are the basic options we will use to create the constraint. These
378 ## may be altered depending on the parent type, etc.
381 name => $name || '__ANON__',
382 package_defined_in => $pkg_defined_in,
384 ($check ? (constraint => $check) : ()),
385 ($message ? (message => $message) : ()),
386 ($optimized ? (optimized => $optimized) : ()),
389 ## If we have a parent we make sure to instantiate this new type constraint
390 ## as a subclass of the parents meta class. We need to see if the $parent
391 ## is already a blessed TC or if we need to go make it based on it's name
397 and $parent = blessed $parent ? $parent:find_or_parse_type_constraint($parent)
399 ## creating the child is a job we delegate to the parent, since each
400 ## parent may have local customization needs to influence it's child.
401 $constraint = $parent->create_childtype(%opts);
403 ## If for some reason the above couldn't create a type constraint, let's
404 ## make sure to create something.
405 $constraint = Moose::Meta::TypeConstraint->new(%opts);
408 ## Unless we have a request to make an anonynmous constraint, let's add it
409 ## to the $REGISTRY so that it gets cached for quicker lookups next time
411 $REGISTRY->add_type_constraint($constraint)
417 sub _install_type_coercions ($$) {
418 my ($type_name, $coercion_map) = @_;
419 my $type = find_type_constraint($type_name);
421 || Moose->throw_error("Cannot find type '$type_name', perhaps you forgot to load it.");
422 if ($type->has_coercion) {
423 $type->coercion->add_type_coercions(@$coercion_map);
426 my $type_coercion = Moose::Meta::TypeCoercion->new(
427 type_coercion_map => $coercion_map,
428 type_constraint => $type
430 $type->coercion($type_coercion);
434 ## --------------------------------------------------------
435 ## type notation parsing ...
436 ## --------------------------------------------------------
439 # All I have to say is mugwump++ cause I know
440 # do not even have enough regexp-fu to be able
441 # to have written this (I can only barely
442 # understand it as it is)
447 my $valid_chars = qr{[\w:]};
448 my $type_atom = qr{ $valid_chars+ };
452 my $type = qr{ $valid_chars+ (?: \[ \s* (??{$any}) \s* \] )? }x;
453 my $type_capture_parts = qr{ ($valid_chars+) (?: \[ \s* ((??{$any})) \s* \] )? }x;
454 my $type_with_parameter = qr{ $valid_chars+ \[ \s* (??{$any}) \s* \] }x;
456 my $op_union = qr{ \s* \| \s* }x;
457 my $union = qr{ $type (?: $op_union $type )+ }x;
459 $any = qr{ $type | $union }x;
461 sub _parse_parameterized_type_constraint {
462 { no warnings 'void'; $any; } # force capture of interpolated lexical
463 $_[0] =~ m{ $type_capture_parts }x;
467 sub _detect_parameterized_type_constraint {
468 { no warnings 'void'; $any; } # force capture of interpolated lexical
469 $_[0] =~ m{ ^ $type_with_parameter $ }x;
472 sub _parse_type_constraint_union {
473 { no warnings 'void'; $any; } # force capture of interpolated lexical
476 while ( $given =~ m{ \G (?: $op_union )? ($type) }gcx ) {
479 (pos($given) eq length($given))
480 || Moose->throw_error("'$given' didn't parse (parse-pos="
488 sub _detect_type_constraint_union {
489 { no warnings 'void'; $any; } # force capture of interpolated lexical
490 $_[0] =~ m{^ $type $op_union $type ( $op_union .* )? $}x;
494 ## --------------------------------------------------------
495 # define some basic built-in types
496 ## --------------------------------------------------------
498 type 'Any' => where { 1 }; # meta-type including all
499 type 'Item' => where { 1 }; # base-type
501 subtype 'Undef' => as 'Item' => where { !defined($_) };
502 subtype 'Defined' => as 'Item' => where { defined($_) };
506 => where { !defined($_) || $_ eq "" || "$_" eq '1' || "$_" eq '0' };
510 => where { !ref($_) }
511 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Value;
516 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Ref;
521 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Str;
525 => where { Scalar::Util::looks_like_number($_) }
526 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Num;
530 => where { "$_" =~ /^-?[0-9]+$/ }
531 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Int;
533 subtype 'ScalarRef' => as 'Ref' => where { ref($_) eq 'SCALAR' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ScalarRef;
534 subtype 'CodeRef' => as 'Ref' => where { ref($_) eq 'CODE' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::CodeRef;
535 subtype 'RegexpRef' => as 'Ref' => where { ref($_) eq 'Regexp' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::RegexpRef;
536 subtype 'GlobRef' => as 'Ref' => where { ref($_) eq 'GLOB' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::GlobRef;
539 # scalar filehandles are GLOB refs,
540 # but a GLOB ref is not always a filehandle
543 => where { Scalar::Util::openhandle($_) || ( blessed($_) && $_->isa("IO::Handle") ) }
544 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::FileHandle;
547 # blessed(qr/.../) returns true,.. how odd
550 => where { blessed($_) && blessed($_) ne 'Regexp' }
551 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Object;
555 => where { $_->can('does') }
556 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Role;
558 my $_class_name_checker = sub {
563 => where { Class::MOP::is_class_loaded($_) }
564 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ClassName;
566 ## --------------------------------------------------------
567 # parameterizable types ...
569 $REGISTRY->add_type_constraint(
570 Moose::Meta::TypeConstraint::Parameterizable->new(
572 package_defined_in => __PACKAGE__,
573 parent => find_type_constraint('Ref'),
574 constraint => sub { ref($_) eq 'ARRAY' },
575 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::ArrayRef,
576 constraint_generator => sub {
577 my $type_parameter = shift;
578 my $check = $type_parameter->_compiled_type_constraint;
580 foreach my $x (@$_) {
581 ($check->($x)) || return
588 $REGISTRY->add_type_constraint(
589 Moose::Meta::TypeConstraint::Parameterizable->new(
591 package_defined_in => __PACKAGE__,
592 parent => find_type_constraint('Ref'),
593 constraint => sub { ref($_) eq 'HASH' },
594 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::HashRef,
595 constraint_generator => sub {
596 my $type_parameter = shift;
597 my $check = $type_parameter->_compiled_type_constraint;
599 foreach my $x (values %$_) {
600 ($check->($x)) || return
607 $REGISTRY->add_type_constraint(
608 Moose::Meta::TypeConstraint::Parameterizable->new(
610 package_defined_in => __PACKAGE__,
611 parent => find_type_constraint('Item'),
612 constraint => sub { 1 },
613 constraint_generator => sub {
614 my $type_parameter = shift;
615 my $check = $type_parameter->_compiled_type_constraint;
617 return 1 if not(defined($_)) || $check->($_);
624 my @PARAMETERIZABLE_TYPES = map {
625 $REGISTRY->get_type_constraint($_)
626 } qw[ArrayRef HashRef Maybe];
628 sub get_all_parameterizable_types { @PARAMETERIZABLE_TYPES }
629 sub add_parameterizable_type {
631 (blessed $type && $type->isa('Moose::Meta::TypeConstraint::Parameterizable'))
632 || Moose->throw_error("Type must be a Moose::Meta::TypeConstraint::Parameterizable not $type");
633 push @PARAMETERIZABLE_TYPES => $type;
636 ## --------------------------------------------------------
637 # end of built-in types ...
638 ## --------------------------------------------------------
641 my @BUILTINS = list_all_type_constraints();
642 sub list_all_builtin_type_constraints { @BUILTINS }
653 Moose::Util::TypeConstraints - Type constraint system for Moose
657 use Moose::Util::TypeConstraints;
659 type 'Num' => where { Scalar::Util::looks_like_number($_) };
665 subtype 'NaturalLessThanTen'
668 => message { "This number ($_) is not less than ten!" };
674 enum 'RGBColors' => qw(red green blue);
678 This module provides Moose with the ability to create custom type
679 contraints to be used in attribute definition.
681 =head2 Important Caveat
683 This is B<NOT> a type system for Perl 5. These are type constraints,
684 and they are not used by Moose unless you tell it to. No type
685 inference is performed, expression are not typed, etc. etc. etc.
687 This is simply a means of creating small constraint functions which
688 can be used to simplify your own type-checking code, with the added
689 side benefit of making your intentions clearer through self-documentation.
691 =head2 Slightly Less Important Caveat
693 It is B<always> a good idea to quote your type and subtype names.
695 This is to prevent perl from trying to execute the call as an indirect
696 object call. This issue only seems to come up when you have a subtype
697 the same name as a valid class, but when the issue does arise it tends
698 to be quite annoying to debug.
700 So for instance, this:
702 subtype DateTime => as Object => where { $_->isa('DateTime') };
704 will I<Just Work>, while this:
707 subtype DateTime => as Object => where { $_->isa('DateTime') };
709 will fail silently and cause many headaches. The simple way to solve
710 this, as well as future proof your subtypes from classes which have
711 yet to have been created yet, is to simply do this:
714 subtype 'DateTime' => as 'Object' => where { $_->isa('DateTime') };
716 =head2 Default Type Constraints
718 This module also provides a simple hierarchy for Perl 5 types, here is
719 that hierarchy represented visually.
743 B<NOTE:> Any type followed by a type parameter C<[`a]> can be
744 parameterized, this means you can say:
746 ArrayRef[Int] # an array of integers
747 HashRef[CodeRef] # a hash of str to CODE ref mappings
748 Maybe[Str] # value may be a string, may be undefined
750 B<NOTE:> Unless you parameterize a type, then it is invalid to
751 include the square brackets. I.e. C<ArrayRef[]> will be
752 literally interpreted as a type name.
754 B<NOTE:> The C<Undef> type constraint for the most part works
755 correctly now, but edge cases may still exist, please use it
758 B<NOTE:> The C<ClassName> type constraint does a complex package
759 existence check. This means that your class B<must> be loaded for
760 this type constraint to pass. I know this is not ideal for all,
761 but it is a saner restriction than most others.
763 =head2 Type Constraint Naming
765 Since the types created by this module are global, it is suggested
766 that you namespace your types just as you would namespace your
767 modules. So instead of creating a I<Color> type for your B<My::Graphics>
768 module, you would call the type I<My::Graphics::Color> instead.
770 =head2 Use with Other Constraint Modules
772 This module should play fairly nicely with other constraint
773 modules with only some slight tweaking. The C<where> clause
774 in types is expected to be a C<CODE> reference which checks
775 it's first argument and returns a boolean. Since most constraint
776 modules work in a similar way, it should be simple to adapt
777 them to work with Moose.
779 For instance, this is how you could use it with
780 L<Declare::Constraints::Simple> to declare a completely new type.
782 type 'HashOfArrayOfObjects'
785 -values => IsArrayRef( IsObject ));
787 For more examples see the F<t/200_examples/204_example_w_DCS.t>
790 Here is an example of using L<Test::Deep> and it's non-test
791 related C<eq_deeply> function.
793 type 'ArrayOfHashOfBarsAndRandomNumbers'
796 array_each(subhashof({
798 random_number => ignore()
802 For a complete example see the
803 F<t/200_examples/205_example_w_TestDeep.t> test file.
807 =head2 Type Constraint Constructors
809 The following functions are used to create type constraints.
810 They will then register the type constraints in a global store
811 where Moose can get to them if it needs to.
813 See the L<SYNOPSIS> for an example of how to use these.
817 =item B<type ($name, $where_clause)>
819 This creates a base type, which has no parent.
821 =item B<subtype ($name, $parent, $where_clause, ?$message)>
823 This creates a named subtype.
825 =item B<subtype ($parent, $where_clause, ?$message)>
827 This creates an unnamed subtype and will return the type
828 constraint meta-object, which will be an instance of
829 L<Moose::Meta::TypeConstraint>.
831 =item B<class_type ($class, ?$options)>
833 Creates a type constraint with the name C<$class> and the metaclass
834 L<Moose::Meta::TypeConstraint::Class>.
836 =item B<role_type ($role, ?$options)>
838 Creates a type constraint with the name C<$role> and the metaclass
839 L<Moose::Meta::TypeConstraint::Role>.
841 =item B<enum ($name, @values)>
843 This will create a basic subtype for a given set of strings.
844 The resulting constraint will be a subtype of C<Str> and
845 will match any of the items in C<@values>. It is case sensitive.
846 See the L<SYNOPSIS> for a simple example.
848 B<NOTE:> This is not a true proper enum type, it is simple
849 a convient constraint builder.
851 =item B<enum (\@values)>
853 If passed an ARRAY reference instead of the C<$name>, C<@values> pair,
854 this will create an unnamed enum. This can then be used in an attribute
857 has 'sort_order' => (
859 isa => enum([qw[ ascending descending ]]),
864 This is just sugar for the type constraint construction syntax.
868 This is just sugar for the type constraint construction syntax.
870 Takes a block/code ref as an argument. When the type constraint is
871 tested, the supplied code is run with the value to be tested in
872 $_. This block should return true or false to indicate whether or not
873 the constraint check passed.
877 This is just sugar for the type constraint construction syntax.
879 Takes a block/code ref as an argument. When the type constraint fails,
880 then the code block is run (with the value provided in $_). This code
881 ref should return a string, which will be used in the text of the
886 This can be used to define a "hand optimized" version of your
887 type constraint which can be used to avoid traversing a subtype
888 constraint heirarchy.
890 B<NOTE:> You should only use this if you know what you are doing,
891 all the built in types use this, so your subtypes (assuming they
892 are shallow) will not likely need to use this.
896 =head2 Type Coercion Constructors
898 Type constraints can also contain type coercions as well. If you
899 ask your accessor to coerce, then Moose will run the type-coercion
900 code first, followed by the type constraint check. This feature
901 should be used carefully as it is very powerful and could easily
902 take off a limb if you are not careful.
904 See the L<SYNOPSIS> for an example of how to use these.
912 This is just sugar for the type coercion construction syntax.
916 This is just sugar for the type coercion construction syntax.
920 =head2 Type Constraint Construction & Locating
924 =item B<normalize_type_constraint_name ($type_constraint_name)>
926 Given a string that is expected to match a type constraint, will normalize the
927 string so that extra whitespace and newlines are removed.
929 =item B<create_type_constraint_union ($pipe_seperated_types | @type_constraint_names)>
931 Given string with C<$pipe_seperated_types> or a list of C<@type_constraint_names>,
932 this will return a L<Moose::Meta::TypeConstraint::Union> instance.
934 =item B<create_parameterized_type_constraint ($type_name)>
936 Given a C<$type_name> in the form of:
938 BaseType[ContainerType]
940 this will extract the base type and container type and build an instance of
941 L<Moose::Meta::TypeConstraint::Parameterized> for it.
943 =item B<create_class_type_constraint ($class, ?$options)>
945 Given a class name it will create a new L<Moose::Meta::TypeConstraint::Class>
946 object for that class name.
948 =item B<create_role_type_constraint ($role, ?$options)>
950 Given a role name it will create a new L<Moose::Meta::TypeConstraint::Role>
951 object for that role name.
953 =item B<create_enum_type_constraint ($name, $values)>
955 =item B<find_or_parse_type_constraint ($type_name)>
957 This will attempt to find or create a type constraint given the a C<$type_name>.
958 If it cannot find it in the registry, it will see if it should be a union or
959 container type an create one if appropriate
961 =item B<find_or_create_type_constraint ($type_name, ?$options_for_anon_type)>
963 This function will first call C<find_or_parse_type_constraint> with the type name.
965 If no type is found or created, but C<$options_for_anon_type> are provided, it
966 will create the corresponding type.
968 This was used by the C<does> and C<isa> parameters to L<Moose::Meta::Attribute>
969 and are now superseded by C<find_or_create_isa_type_constraint> and
970 C<find_or_create_does_type_constraint>.
972 =item B<find_or_create_isa_type_constraint ($type_name)>
974 =item B<find_or_create_does_type_constraint ($type_name)>
976 Attempts to parse the type name using L<find_or_parse_type_constraint> and if
977 no appropriate constraint is found will create a new anonymous one.
979 The C<isa> variant will use C<create_class_type_constraint> and the C<does>
980 variant will use C<create_role_type_constraint>.
982 =item B<find_type_constraint ($type_name)>
984 This function can be used to locate a specific type constraint
985 meta-object, of the class L<Moose::Meta::TypeConstraint> or a
986 derivative. What you do with it from there is up to you :)
988 =item B<register_type_constraint ($type_object)>
990 This function will register a named type constraint with the type registry.
992 =item B<get_type_constraint_registry>
994 Fetch the L<Moose::Meta::TypeConstraint::Registry> object which
995 keeps track of all type constraints.
997 =item B<list_all_type_constraints>
999 This will return a list of type constraint names, you can then
1000 fetch them using C<find_type_constraint ($type_name)> if you
1003 =item B<list_all_builtin_type_constraints>
1005 This will return a list of builtin type constraints, meaning,
1006 those which are defined in this module. See the section
1007 labeled L<Default Type Constraints> for a complete list.
1009 =item B<export_type_constraints_as_functions>
1011 This will export all the current type constraints as functions
1012 into the caller's namespace. Right now, this is mostly used for
1013 testing, but it might prove useful to others.
1015 =item B<get_all_parameterizable_types>
1017 This returns all the parameterizable types that have been registered.
1019 =item B<add_parameterizable_type ($type)>
1021 Adds C<$type> to the list of parameterizable types
1025 =head2 Namespace Management
1031 This will remove all the type constraint keywords from the
1032 calling class namespace.
1038 All complex software has bugs lurking in it, and this module is no
1039 exception. If you find a bug please either email me, or add the bug
1044 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1046 =head1 COPYRIGHT AND LICENSE
1048 Copyright 2006-2008 by Infinity Interactive, Inc.
1050 L<http://www.iinteractive.com>
1052 This library is free software; you can redistribute it and/or modify
1053 it under the same terms as Perl itself.