2 package Moose::Util::TypeConstraints;
8 use Scalar::Util 'blessed';
11 our $VERSION = '0.57';
12 $VERSION = eval $VERSION;
13 our $AUTHORITY = 'cpan:STEVAN';
15 ## --------------------------------------------------------
16 # Prototyped subs must be predeclared because we have a
17 # circular dependency with Moose::Meta::Attribute et. al.
18 # so in case of us being use'd first the predeclaration
19 # ensures the prototypes are in scope when consumers are
22 # creation and location
23 sub find_type_constraint ($);
24 sub register_type_constraint ($);
25 sub find_or_create_type_constraint ($;$);
26 sub find_or_parse_type_constraint ($);
27 sub find_or_create_isa_type_constraint ($);
28 sub find_or_create_does_type_constraint ($);
29 sub create_type_constraint_union (@);
30 sub create_parameterized_type_constraint ($);
31 sub create_class_type_constraint ($;$);
32 sub create_role_type_constraint ($;$);
33 sub create_enum_type_constraint ($$);
49 sub _create_type_constraint ($$$;$$);
50 sub _install_type_coercions ($$);
52 ## --------------------------------------------------------
54 use Moose::Meta::TypeConstraint;
55 use Moose::Meta::TypeConstraint::Union;
56 use Moose::Meta::TypeConstraint::Parameterized;
57 use Moose::Meta::TypeConstraint::Parameterizable;
58 use Moose::Meta::TypeConstraint::Class;
59 use Moose::Meta::TypeConstraint::Role;
60 use Moose::Meta::TypeConstraint::Enum;
61 use Moose::Meta::TypeCoercion;
62 use Moose::Meta::TypeCoercion::Union;
63 use Moose::Meta::TypeConstraint::Registry;
64 use Moose::Util::TypeConstraints::OptimizedConstraints;
66 Moose::Exporter->setup_import_methods(
69 type subtype class_type role_type as where message optimize_as
73 register_type_constraint )
78 ## --------------------------------------------------------
79 ## type registry and some useful functions for it
80 ## --------------------------------------------------------
82 my $REGISTRY = Moose::Meta::TypeConstraint::Registry->new;
84 sub get_type_constraint_registry { $REGISTRY }
85 sub list_all_type_constraints { keys %{$REGISTRY->type_constraints} }
86 sub export_type_constraints_as_functions {
89 foreach my $constraint (keys %{$REGISTRY->type_constraints}) {
90 my $tc = $REGISTRY->get_type_constraint($constraint)->_compiled_type_constraint;
91 *{"${pkg}::${constraint}"} = sub { $tc->($_[0]) ? 1 : undef }; # the undef is for compat
95 sub create_type_constraint_union (@) {
96 my @type_constraint_names;
98 if (scalar @_ == 1 && _detect_type_constraint_union($_[0])) {
99 @type_constraint_names = _parse_type_constraint_union($_[0]);
102 @type_constraint_names = @_;
105 (scalar @type_constraint_names >= 2)
106 || Moose->throw_error("You must pass in at least 2 type names to make a union");
108 my @type_constraints = sort {$a->name cmp $b->name} map {
109 find_or_parse_type_constraint($_) ||
110 Moose->throw_error("Could not locate type constraint ($_) for the union");
111 } @type_constraint_names;
113 return Moose::Meta::TypeConstraint::Union->new(
114 type_constraints => \@type_constraints
118 sub create_parameterized_type_constraint ($) {
119 my $type_constraint_name = shift;
120 my ($base_type, $type_parameter_str) = _parse_parameterized_type_constraint($type_constraint_name);
122 (defined $base_type && defined $type_parameter_str)
123 || Moose->throw_error("Could not parse type name ($type_constraint_name) correctly");
125 if ($REGISTRY->has_type_constraint($base_type)) {
126 my $base_type_tc = $REGISTRY->get_type_constraint($base_type);
127 return _create_parameterized_type_constraint(
132 Moose->throw_error("Could not locate the base type ($base_type)");
136 sub _create_parameterized_type_constraint {
137 my ($base_type_tc, $type_parameter_str) = @_;
138 if($base_type_tc->can('parameterize')) {
139 my @type_parameters_tc = $base_type_tc->parse_parameter_str($type_parameter_str);
140 return $base_type_tc->parameterize( @type_parameters_tc);
142 return Moose::Meta::TypeConstraint::Parameterized->new(
143 name => $base_type_tc->name .'['. $type_parameter_str .']',
144 parent => $base_type_tc,
145 type_parameter => find_or_create_isa_type_constraint($type_parameter_str),
150 #should we also support optimized checks?
151 sub create_class_type_constraint ($;$) {
152 my ( $class, $options ) = @_;
154 # too early for this check
155 #find_type_constraint("ClassName")->check($class)
156 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
164 $options{name} ||= "__ANON__";
166 Moose::Meta::TypeConstraint::Class->new( %options );
169 sub create_role_type_constraint ($;$) {
170 my ( $role, $options ) = @_;
172 # too early for this check
173 #find_type_constraint("ClassName")->check($class)
174 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
182 $options{name} ||= "__ANON__";
184 Moose::Meta::TypeConstraint::Role->new( %options );
188 sub find_or_create_type_constraint ($;$) {
189 my ( $type_constraint_name, $options_for_anon_type ) = @_;
191 if ( my $constraint = find_or_parse_type_constraint($type_constraint_name) ) {
194 elsif ( defined $options_for_anon_type ) {
196 # if there is no $options_for_anon_type
197 # specified, then we assume they don't
198 # want to create one, and return nothing.
200 # otherwise assume that we should create
201 # an ANON type with the $options_for_anon_type
202 # options which can be passed in. It should
203 # be noted that these don't get registered
204 # so we need to return it.
206 return Moose::Meta::TypeConstraint->new(
208 %{$options_for_anon_type}
215 sub find_or_create_isa_type_constraint ($) {
216 my $type_constraint_name = shift;
217 find_or_parse_type_constraint($type_constraint_name) || create_class_type_constraint($type_constraint_name)
220 sub find_or_create_does_type_constraint ($) {
221 my $type_constraint_name = shift;
222 find_or_parse_type_constraint($type_constraint_name) || create_role_type_constraint($type_constraint_name)
225 sub find_or_parse_type_constraint ($) {
226 my $type_constraint_name = shift;
229 if ($constraint = find_type_constraint($type_constraint_name)) {
231 } elsif (_detect_type_constraint_union($type_constraint_name)) {
232 $constraint = create_type_constraint_union($type_constraint_name);
233 } elsif (_detect_parameterized_type_constraint($type_constraint_name)) {
234 $constraint = create_parameterized_type_constraint($type_constraint_name);
239 $REGISTRY->add_type_constraint($constraint);
243 ## --------------------------------------------------------
244 ## exported functions ...
245 ## --------------------------------------------------------
247 sub find_type_constraint ($) {
250 if ( blessed $type and $type->isa("Moose::Meta::TypeConstraint") ) {
254 return unless $REGISTRY->has_type_constraint($type);
255 return $REGISTRY->get_type_constraint($type);
259 sub register_type_constraint ($) {
260 my $constraint = shift;
261 Moose->throw_error("can't register an unnamed type constraint") unless defined $constraint->name;
262 $REGISTRY->add_type_constraint($constraint);
269 splice(@_, 1, 0, undef);
270 goto &_create_type_constraint;
273 sub subtype ($$;$$$) {
275 # this adds an undef for the name
276 # if this is an anon-subtype:
277 # subtype(Num => where { $_ % 2 == 0 }) # anon 'even' subtype
278 # but if the last arg is not a code
279 # ref then it is a subtype alias:
280 # subtype(MyNumbers => as Num); # now MyNumbers is the same as Num
281 # ... yeah I know it's ugly code
283 unshift @_ => undef if scalar @_ <= 2 && ('CODE' eq ref($_[1]));
284 goto &_create_type_constraint;
287 sub class_type ($;$) {
288 register_type_constraint(
289 create_class_type_constraint(
291 ( defined($_[1]) ? $_[1] : () ),
296 sub role_type ($;$) {
297 register_type_constraint(
298 create_role_type_constraint(
300 ( defined($_[1]) ? $_[1] : () ),
306 my ($type_name, @coercion_map) = @_;
307 _install_type_coercions($type_name, \@coercion_map);
311 sub from ($) { $_[0] }
312 sub where (&) { $_[0] }
313 sub via (&) { $_[0] }
315 sub message (&) { +{ message => $_[0] } }
316 sub optimize_as (&) { +{ optimized => $_[0] } }
319 my ($type_name, @values) = @_;
321 # if only an array-ref is passed then
322 # you get an anon-enum
324 if (ref $type_name eq 'ARRAY' && !@values) {
325 @values = @$type_name;
328 (scalar @values >= 2)
329 || Moose->throw_error("You must have at least two values to enumerate through");
330 my %valid = map { $_ => 1 } @values;
332 register_type_constraint(
333 create_enum_type_constraint(
340 sub create_enum_type_constraint ($$) {
341 my ( $type_name, $values ) = @_;
343 Moose::Meta::TypeConstraint::Enum->new(
344 name => $type_name || '__ANON__',
349 ## --------------------------------------------------------
350 ## desugaring functions ...
351 ## --------------------------------------------------------
353 sub _create_type_constraint ($$$;$$) {
358 my ($message, $optimized);
360 $message = $_->{message} if exists $_->{message};
361 $optimized = $_->{optimized} if exists $_->{optimized};
364 my $pkg_defined_in = scalar(caller(0));
367 my $type = $REGISTRY->get_type_constraint($name);
369 ($type->_package_defined_in eq $pkg_defined_in)
370 || confess ("The type constraint '$name' has already been created in "
371 . $type->_package_defined_in . " and cannot be created again in "
376 my $class = "Moose::Meta::TypeConstraint";
378 # FIXME should probably not be a special case
379 if ( defined $parent and $parent = find_or_parse_type_constraint($parent) ) {
380 $class = "Moose::Meta::TypeConstraint::Parameterizable"
381 if $parent->isa("Moose::Meta::TypeConstraint::Parameterizable");
384 my $constraint = $class->new(
385 name => $name || '__ANON__',
386 package_defined_in => $pkg_defined_in,
388 ($parent ? (parent => $parent ) : ()),
389 ($check ? (constraint => $check) : ()),
390 ($message ? (message => $message) : ()),
391 ($optimized ? (optimized => $optimized) : ()),
395 # if we have a type constraint union, and no
396 # type check, this means we are just aliasing
397 # the union constraint, which means we need to
398 # handle this differently.
400 if (not(defined $check)
401 && $parent->isa('Moose::Meta::TypeConstraint::Union')
402 && $parent->has_coercion
404 $constraint->coercion(Moose::Meta::TypeCoercion::Union->new(
405 type_constraint => $parent
409 $REGISTRY->add_type_constraint($constraint)
415 sub _install_type_coercions ($$) {
416 my ($type_name, $coercion_map) = @_;
417 my $type = find_type_constraint($type_name);
419 || Moose->throw_error("Cannot find type '$type_name', perhaps you forgot to load it.");
420 if ($type->has_coercion) {
421 $type->coercion->add_type_coercions(@$coercion_map);
424 my $type_coercion = Moose::Meta::TypeCoercion->new(
425 type_coercion_map => $coercion_map,
426 type_constraint => $type
428 $type->coercion($type_coercion);
432 ## --------------------------------------------------------
433 ## type notation parsing ...
434 ## --------------------------------------------------------
437 # All I have to say is mugwump++ cause I know
438 # do not even have enough regexp-fu to be able
439 # to have written this (I can only barely
440 # understand it as it is)
445 my $valid_chars = qr{[\w:]};
446 my $type_atom = qr{ $valid_chars+ };
450 my $type = qr{ $valid_chars+ (?: \[ \s* (??{$any}) \s* \] )? }x;
451 my $type_capture_parts = qr{ ($valid_chars+) (?: \[ \s* ((??{$any})) \s* \] )? }x;
452 my $type_with_parameter = qr{ $valid_chars+ \[ \s* (??{$any}) \s* \] }x;
454 my $op_union = qr{ \s* \| \s* }x;
455 my $union = qr{ $type (?: $op_union $type )+ }x;
457 ## New Stuff for structured types.
459 my $indirection = qr{=>};
460 my $divider_ops = qr{ $comma | $indirection }x;
461 my $structure_divider = qr{\s* $divider_ops \s*}x;
462 my $structure_elements = qr{ ($type $structure_divider*)+ }x;
464 $any = qr{ $type | $union | $structure_elements }x;
466 sub _parse_parameterized_type_constraint {
467 { no warnings 'void'; $any; } # force capture of interpolated lexical
468 my($base, $elements) = ($_[0] =~ m{ $type_capture_parts }x);
469 return ($base, split($structure_divider, $elements));
472 sub _detect_parameterized_type_constraint {
473 { no warnings 'void'; $any; } # force capture of interpolated lexical
474 $_[0] =~ m{ ^ $type_with_parameter $ }x;
477 sub _parse_type_constraint_union {
478 { no warnings 'void'; $any; } # force capture of interpolated lexical
481 while ( $given =~ m{ \G (?: $op_union )? ($type) }gcx ) {
484 (pos($given) eq length($given))
485 || Moose->throw_error("'$given' didn't parse (parse-pos="
493 sub _detect_type_constraint_union {
494 { no warnings 'void'; $any; } # force capture of interpolated lexical
495 $_[0] =~ m{^ $type $op_union $type ( $op_union .* )? $}x;
499 ## --------------------------------------------------------
500 # define some basic built-in types
501 ## --------------------------------------------------------
503 type 'Any' => where { 1 }; # meta-type including all
504 type 'Item' => where { 1 }; # base-type
506 subtype 'Undef' => as 'Item' => where { !defined($_) };
507 subtype 'Defined' => as 'Item' => where { defined($_) };
511 => where { !defined($_) || $_ eq "" || "$_" eq '1' || "$_" eq '0' };
515 => where { !ref($_) }
516 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Value;
521 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Ref;
526 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Str;
530 => where { Scalar::Util::looks_like_number($_) }
531 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Num;
535 => where { "$_" =~ /^-?[0-9]+$/ }
536 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Int;
538 subtype 'ScalarRef' => as 'Ref' => where { ref($_) eq 'SCALAR' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ScalarRef;
539 subtype 'CodeRef' => as 'Ref' => where { ref($_) eq 'CODE' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::CodeRef;
540 subtype 'RegexpRef' => as 'Ref' => where { ref($_) eq 'Regexp' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::RegexpRef;
541 subtype 'GlobRef' => as 'Ref' => where { ref($_) eq 'GLOB' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::GlobRef;
544 # scalar filehandles are GLOB refs,
545 # but a GLOB ref is not always a filehandle
548 => where { Scalar::Util::openhandle($_) || ( blessed($_) && $_->isa("IO::Handle") ) }
549 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::FileHandle;
552 # blessed(qr/.../) returns true,.. how odd
555 => where { blessed($_) && blessed($_) ne 'Regexp' }
556 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Object;
560 => where { $_->can('does') }
561 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Role;
563 my $_class_name_checker = sub {
568 => where { Class::MOP::is_class_loaded($_) }
569 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ClassName;
571 ## --------------------------------------------------------
572 # parameterizable types ...
574 $REGISTRY->add_type_constraint(
575 Moose::Meta::TypeConstraint::Parameterizable->new(
577 package_defined_in => __PACKAGE__,
578 parent => find_type_constraint('Ref'),
579 constraint => sub { ref($_) eq 'ARRAY' },
580 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::ArrayRef,
581 constraint_generator => sub {
582 my $type_parameter = shift;
583 my $check = $type_parameter->_compiled_type_constraint;
585 foreach my $x (@$_) {
586 ($check->($x)) || return
593 $REGISTRY->add_type_constraint(
594 Moose::Meta::TypeConstraint::Parameterizable->new(
596 package_defined_in => __PACKAGE__,
597 parent => find_type_constraint('Ref'),
598 constraint => sub { ref($_) eq 'HASH' },
599 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::HashRef,
600 constraint_generator => sub {
601 my $type_parameter = shift;
602 my $check = $type_parameter->_compiled_type_constraint;
604 foreach my $x (values %$_) {
605 ($check->($x)) || return
612 $REGISTRY->add_type_constraint(
613 Moose::Meta::TypeConstraint::Parameterizable->new(
615 package_defined_in => __PACKAGE__,
616 parent => find_type_constraint('Item'),
617 constraint => sub { 1 },
618 constraint_generator => sub {
619 my $type_parameter = shift;
620 my $check = $type_parameter->_compiled_type_constraint;
622 return 1 if not(defined($_)) || $check->($_);
629 my @PARAMETERIZABLE_TYPES = map {
630 $REGISTRY->get_type_constraint($_)
631 } qw[ArrayRef HashRef Maybe];
633 sub get_all_parameterizable_types { @PARAMETERIZABLE_TYPES }
634 sub add_parameterizable_type {
636 (blessed $type && $type->isa('Moose::Meta::TypeConstraint::Parameterizable'))
637 || Moose->throw_error("Type must be a Moose::Meta::TypeConstraint::Parameterizable not $type");
638 push @PARAMETERIZABLE_TYPES => $type;
641 ## --------------------------------------------------------
642 # end of built-in types ...
643 ## --------------------------------------------------------
646 my @BUILTINS = list_all_type_constraints();
647 sub list_all_builtin_type_constraints { @BUILTINS }
658 Moose::Util::TypeConstraints - Type constraint system for Moose
662 use Moose::Util::TypeConstraints;
664 type 'Num' => where { Scalar::Util::looks_like_number($_) };
670 subtype 'NaturalLessThanTen'
673 => message { "This number ($_) is not less than ten!" };
679 enum 'RGBColors' => qw(red green blue);
683 This module provides Moose with the ability to create custom type
684 contraints to be used in attribute definition.
686 =head2 Important Caveat
688 This is B<NOT> a type system for Perl 5. These are type constraints,
689 and they are not used by Moose unless you tell it to. No type
690 inference is performed, expression are not typed, etc. etc. etc.
692 This is simply a means of creating small constraint functions which
693 can be used to simplify your own type-checking code, with the added
694 side benefit of making your intentions clearer through self-documentation.
696 =head2 Slightly Less Important Caveat
698 It is B<always> a good idea to quote your type and subtype names.
700 This is to prevent perl from trying to execute the call as an indirect
701 object call. This issue only seems to come up when you have a subtype
702 the same name as a valid class, but when the issue does arise it tends
703 to be quite annoying to debug.
705 So for instance, this:
707 subtype DateTime => as Object => where { $_->isa('DateTime') };
709 will I<Just Work>, while this:
712 subtype DateTime => as Object => where { $_->isa('DateTime') };
714 will fail silently and cause many headaches. The simple way to solve
715 this, as well as future proof your subtypes from classes which have
716 yet to have been created yet, is to simply do this:
719 subtype 'DateTime' => as 'Object' => where { $_->isa('DateTime') };
721 =head2 Default Type Constraints
723 This module also provides a simple hierarchy for Perl 5 types, here is
724 that hierarchy represented visually.
748 B<NOTE:> Any type followed by a type parameter C<[`a]> can be
749 parameterized, this means you can say:
751 ArrayRef[Int] # an array of intergers
752 HashRef[CodeRef] # a hash of str to CODE ref mappings
753 Maybe[Str] # value may be a string, may be undefined
755 B<NOTE:> Unless you parameterize a type, then it is invalid to
756 include the square brackets. I.e. C<ArrayRef[]> will be
757 literally interpreted as a type name.
759 B<NOTE:> The C<Undef> type constraint for the most part works
760 correctly now, but edge cases may still exist, please use it
763 B<NOTE:> The C<ClassName> type constraint does a complex package
764 existence check. This means that your class B<must> be loaded for
765 this type constraint to pass. I know this is not ideal for all,
766 but it is a saner restriction than most others.
768 =head2 Type Constraint Naming
770 Since the types created by this module are global, it is suggested
771 that you namespace your types just as you would namespace your
772 modules. So instead of creating a I<Color> type for your B<My::Graphics>
773 module, you would call the type I<My::Graphics::Color> instead.
775 =head2 Use with Other Constraint Modules
777 This module should play fairly nicely with other constraint
778 modules with only some slight tweaking. The C<where> clause
779 in types is expected to be a C<CODE> reference which checks
780 it's first argument and returns a boolean. Since most constraint
781 modules work in a similar way, it should be simple to adapt
782 them to work with Moose.
784 For instance, this is how you could use it with
785 L<Declare::Constraints::Simple> to declare a completely new type.
787 type 'HashOfArrayOfObjects'
790 -values => IsArrayRef( IsObject ));
792 For more examples see the F<t/200_examples/204_example_w_DCS.t>
795 Here is an example of using L<Test::Deep> and it's non-test
796 related C<eq_deeply> function.
798 type 'ArrayOfHashOfBarsAndRandomNumbers'
801 array_each(subhashof({
803 random_number => ignore()
807 For a complete example see the
808 F<t/200_examples/205_example_w_TestDeep.t> test file.
812 =head2 Type Constraint Constructors
814 The following functions are used to create type constraints.
815 They will then register the type constraints in a global store
816 where Moose can get to them if it needs to.
818 See the L<SYNOPSIS> for an example of how to use these.
822 =item B<type ($name, $where_clause)>
824 This creates a base type, which has no parent.
826 =item B<subtype ($name, $parent, $where_clause, ?$message)>
828 This creates a named subtype.
830 =item B<subtype ($parent, $where_clause, ?$message)>
832 This creates an unnamed subtype and will return the type
833 constraint meta-object, which will be an instance of
834 L<Moose::Meta::TypeConstraint>.
836 =item B<class_type ($class, ?$options)>
838 Creates a type constraint with the name C<$class> and the metaclass
839 L<Moose::Meta::TypeConstraint::Class>.
841 =item B<role_type ($role, ?$options)>
843 Creates a type constraint with the name C<$role> and the metaclass
844 L<Moose::Meta::TypeConstraint::Role>.
846 =item B<enum ($name, @values)>
848 This will create a basic subtype for a given set of strings.
849 The resulting constraint will be a subtype of C<Str> and
850 will match any of the items in C<@values>. It is case sensitive.
851 See the L<SYNOPSIS> for a simple example.
853 B<NOTE:> This is not a true proper enum type, it is simple
854 a convient constraint builder.
856 =item B<enum (\@values)>
858 If passed an ARRAY reference instead of the C<$name>, C<@values> pair,
859 this will create an unnamed enum. This can then be used in an attribute
862 has 'sort_order' => (
864 isa => enum([qw[ ascending descending ]]),
869 This is just sugar for the type constraint construction syntax.
873 This is just sugar for the type constraint construction syntax.
875 Takes a block/code ref as an argument. When the type constraint is
876 tested, the supplied code is run with the value to be tested in
877 $_. This block should return true or false to indicate whether or not
878 the constraint check passed.
882 This is just sugar for the type constraint construction syntax.
884 Takes a block/code ref as an argument. When the type constraint fails,
885 then the code block is run (with the value provided in $_). This code
886 ref should return a string, which will be used in the text of the
891 This can be used to define a "hand optimized" version of your
892 type constraint which can be used to avoid traversing a subtype
893 constraint heirarchy.
895 B<NOTE:> You should only use this if you know what you are doing,
896 all the built in types use this, so your subtypes (assuming they
897 are shallow) will not likely need to use this.
901 =head2 Type Coercion Constructors
903 Type constraints can also contain type coercions as well. If you
904 ask your accessor to coerce, then Moose will run the type-coercion
905 code first, followed by the type constraint check. This feature
906 should be used carefully as it is very powerful and could easily
907 take off a limb if you are not careful.
909 See the L<SYNOPSIS> for an example of how to use these.
917 This is just sugar for the type coercion construction syntax.
921 This is just sugar for the type coercion construction syntax.
925 =head2 Type Constraint Construction & Locating
929 =item B<create_type_constraint_union ($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 =head1 Error Management
1031 If the caller is a Moose metaclass, use its L<Moose::Meta::Class/throw_error>
1032 routine, otherwise use L<Carp/confess>.
1036 =head2 Namespace Management
1042 This will remove all the type constraint keywords from the
1043 calling class namespace.
1049 All complex software has bugs lurking in it, and this module is no
1050 exception. If you find a bug please either email me, or add the bug
1055 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1057 =head1 COPYRIGHT AND LICENSE
1059 Copyright 2006-2008 by Infinity Interactive, Inc.
1061 L<http://www.iinteractive.com>
1063 This library is free software; you can redistribute it and/or modify
1064 it under the same terms as Perl itself.