2 package Moose::Util::TypeConstraints;
8 use List::MoreUtils qw( all );
9 use Scalar::Util 'blessed';
12 our $VERSION = '0.64';
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 maybe_type
51 as where message optimize_as
55 register_type_constraint )
60 ## --------------------------------------------------------
61 ## type registry and some useful functions for it
62 ## --------------------------------------------------------
64 my $REGISTRY = Moose::Meta::TypeConstraint::Registry->new;
66 sub get_type_constraint_registry { $REGISTRY }
67 sub list_all_type_constraints { keys %{$REGISTRY->type_constraints} }
68 sub export_type_constraints_as_functions {
71 foreach my $constraint (keys %{$REGISTRY->type_constraints}) {
72 my $tc = $REGISTRY->get_type_constraint($constraint)->_compiled_type_constraint;
73 *{"${pkg}::${constraint}"} = sub { $tc->($_[0]) ? 1 : undef }; # the undef is for compat
77 sub create_type_constraint_union {
78 my @type_constraint_names;
80 if (scalar @_ == 1 && _detect_type_constraint_union($_[0])) {
81 @type_constraint_names = _parse_type_constraint_union($_[0]);
84 @type_constraint_names = @_;
87 (scalar @type_constraint_names >= 2)
88 || Moose->throw_error("You must pass in at least 2 type names to make a union");
90 my @type_constraints = map {
91 find_or_parse_type_constraint($_) ||
92 Moose->throw_error("Could not locate type constraint ($_) for the union");
93 } @type_constraint_names;
95 return Moose::Meta::TypeConstraint::Union->new(
96 type_constraints => \@type_constraints
100 sub create_parameterized_type_constraint {
101 my $type_constraint_name = shift;
102 my ($base_type, $type_parameter) = _parse_parameterized_type_constraint($type_constraint_name);
104 (defined $base_type && defined $type_parameter)
105 || Moose->throw_error("Could not parse type name ($type_constraint_name) correctly");
107 if ($REGISTRY->has_type_constraint($base_type)) {
108 my $base_type_tc = $REGISTRY->get_type_constraint($base_type);
109 return _create_parameterized_type_constraint(
114 Moose->throw_error("Could not locate the base type ($base_type)");
118 sub _create_parameterized_type_constraint {
119 my ( $base_type_tc, $type_parameter ) = @_;
120 if ( $base_type_tc->can('parameterize') ) {
121 return $base_type_tc->parameterize($type_parameter);
123 return Moose::Meta::TypeConstraint::Parameterized->new(
124 name => $base_type_tc->name . '[' . $type_parameter . ']',
125 parent => $base_type_tc,
126 type_parameter => find_or_create_isa_type_constraint($type_parameter),
131 #should we also support optimized checks?
132 sub create_class_type_constraint {
133 my ( $class, $options ) = @_;
135 # too early for this check
136 #find_type_constraint("ClassName")->check($class)
137 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
145 $options{name} ||= "__ANON__";
147 Moose::Meta::TypeConstraint::Class->new( %options );
150 sub create_role_type_constraint {
151 my ( $role, $options ) = @_;
153 # too early for this check
154 #find_type_constraint("ClassName")->check($class)
155 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
163 $options{name} ||= "__ANON__";
165 Moose::Meta::TypeConstraint::Role->new( %options );
169 sub find_or_create_type_constraint {
170 my ( $type_constraint_name, $options_for_anon_type ) = @_;
172 if ( my $constraint = find_or_parse_type_constraint($type_constraint_name) ) {
175 elsif ( defined $options_for_anon_type ) {
177 # if there is no $options_for_anon_type
178 # specified, then we assume they don't
179 # want to create one, and return nothing.
181 # otherwise assume that we should create
182 # an ANON type with the $options_for_anon_type
183 # options which can be passed in. It should
184 # be noted that these don't get registered
185 # so we need to return it.
187 return Moose::Meta::TypeConstraint->new(
189 %{$options_for_anon_type}
196 sub find_or_create_isa_type_constraint {
197 my $type_constraint_name = shift;
198 find_or_parse_type_constraint($type_constraint_name) || create_class_type_constraint($type_constraint_name)
201 sub find_or_create_does_type_constraint {
202 my $type_constraint_name = shift;
203 find_or_parse_type_constraint($type_constraint_name) || create_role_type_constraint($type_constraint_name)
206 sub find_or_parse_type_constraint {
207 my $type_constraint_name = normalize_type_constraint_name(shift);
210 if ($constraint = find_type_constraint($type_constraint_name)) {
212 } elsif (_detect_type_constraint_union($type_constraint_name)) {
213 $constraint = create_type_constraint_union($type_constraint_name);
214 } elsif (_detect_parameterized_type_constraint($type_constraint_name)) {
215 $constraint = create_parameterized_type_constraint($type_constraint_name);
220 $REGISTRY->add_type_constraint($constraint);
224 sub normalize_type_constraint_name {
225 my $type_constraint_name = shift;
226 $type_constraint_name =~ s/\s//g;
227 return $type_constraint_name;
233 local $Carp::CarpLevel = $Carp::CarpLevel + 1;
234 Carp::confess($error);
237 ## --------------------------------------------------------
238 ## exported functions ...
239 ## --------------------------------------------------------
241 sub find_type_constraint {
244 if ( blessed $type and $type->isa("Moose::Meta::TypeConstraint") ) {
248 return unless $REGISTRY->has_type_constraint($type);
249 return $REGISTRY->get_type_constraint($type);
253 sub register_type_constraint {
254 my $constraint = shift;
255 Moose->throw_error("can't register an unnamed type constraint") unless defined $constraint->name;
256 $REGISTRY->add_type_constraint($constraint);
263 splice(@_, 1, 0, undef);
264 goto &_create_type_constraint;
269 # this adds an undef for the name
270 # if this is an anon-subtype:
271 # subtype(Num => where { $_ % 2 == 0 }) # anon 'even' subtype
273 # subtype(Num => where { $_ % 2 == 0 }) message { "$_ must be an even number" }
275 # but if the last arg is not a code ref then it is a subtype
278 # subtype(MyNumbers => as Num); # now MyNumbers is the same as Num
279 # ... yeah I know it's ugly code
281 unshift @_ => undef if scalar @_ == 2 && ( 'CODE' eq ref( $_[-1] ) );
283 if scalar @_ == 3 && all { ref($_) =~ /^(?:CODE|HASH)$/ } @_[ 1, 2 ];
284 goto &_create_type_constraint;
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_parameter) = @_;
308 register_type_constraint(
309 # $REGISTRY->get_type_constraint('Maybe')
310 # ->get_constraint_for($type_parameter)
311 Moose::Meta::TypeConstraint->new(
312 parent => find_type_constraint('Item'),
314 my $check = $type_parameter->_compiled_type_constraint;
315 return 1 if not(defined($_)) || $check->($_);
323 my ($type_name, @coercion_map) = @_;
324 _install_type_coercions($type_name, \@coercion_map);
329 sub where (&) { $_[0] }
330 sub via (&) { $_[0] }
332 sub message (&) { +{ message => $_[0] } }
333 sub optimize_as (&) { +{ optimized => $_[0] } }
336 my ($type_name, @values) = @_;
338 # if only an array-ref is passed then
339 # you get an anon-enum
341 if (ref $type_name eq 'ARRAY' && !@values) {
342 @values = @$type_name;
345 (scalar @values >= 2)
346 || Moose->throw_error("You must have at least two values to enumerate through");
347 my %valid = map { $_ => 1 } @values;
349 register_type_constraint(
350 create_enum_type_constraint(
357 sub create_enum_type_constraint {
358 my ( $type_name, $values ) = @_;
360 Moose::Meta::TypeConstraint::Enum->new(
361 name => $type_name || '__ANON__',
366 ## --------------------------------------------------------
367 ## desugaring functions ...
368 ## --------------------------------------------------------
370 sub _create_type_constraint ($$$;$$) {
375 my ( $message, $optimized );
377 $message = $_->{message} if exists $_->{message};
378 $optimized = $_->{optimized} if exists $_->{optimized};
381 my $pkg_defined_in = scalar( caller(0) );
383 if ( defined $name ) {
384 my $type = $REGISTRY->get_type_constraint($name);
386 ( $type->_package_defined_in eq $pkg_defined_in )
388 "The type constraint '$name' has already been created in "
389 . $type->_package_defined_in
390 . " and cannot be created again in "
397 package_defined_in => $pkg_defined_in,
399 ( $check ? ( constraint => $check ) : () ),
400 ( $message ? ( message => $message ) : () ),
401 ( $optimized ? ( optimized => $optimized ) : () ),
407 = blessed $parent ? $parent : find_or_parse_type_constraint($parent) )
409 $constraint = $parent->create_child_type(%opts);
412 $constraint = Moose::Meta::TypeConstraint->new(%opts);
415 $REGISTRY->add_type_constraint($constraint)
421 sub _install_type_coercions ($$) {
422 my ($type_name, $coercion_map) = @_;
423 my $type = find_type_constraint($type_name);
425 || Moose->throw_error("Cannot find type '$type_name', perhaps you forgot to load it.");
426 if ($type->has_coercion) {
427 $type->coercion->add_type_coercions(@$coercion_map);
430 my $type_coercion = Moose::Meta::TypeCoercion->new(
431 type_coercion_map => $coercion_map,
432 type_constraint => $type
434 $type->coercion($type_coercion);
438 ## --------------------------------------------------------
439 ## type notation parsing ...
440 ## --------------------------------------------------------
443 # All I have to say is mugwump++ cause I know
444 # do not even have enough regexp-fu to be able
445 # to have written this (I can only barely
446 # understand it as it is)
451 my $valid_chars = qr{[\w:]};
452 my $type_atom = qr{ $valid_chars+ };
456 my $type = qr{ $valid_chars+ (?: \[ \s* (??{$any}) \s* \] )? }x;
457 my $type_capture_parts = qr{ ($valid_chars+) (?: \[ \s* ((??{$any})) \s* \] )? }x;
458 my $type_with_parameter = qr{ $valid_chars+ \[ \s* (??{$any}) \s* \] }x;
460 my $op_union = qr{ \s* \| \s* }x;
461 my $union = qr{ $type (?: $op_union $type )+ }x;
463 $any = qr{ $type | $union }x;
465 sub _parse_parameterized_type_constraint {
466 { no warnings 'void'; $any; } # force capture of interpolated lexical
467 $_[0] =~ m{ $type_capture_parts }x;
471 sub _detect_parameterized_type_constraint {
472 { no warnings 'void'; $any; } # force capture of interpolated lexical
473 $_[0] =~ m{ ^ $type_with_parameter $ }x;
476 sub _parse_type_constraint_union {
477 { no warnings 'void'; $any; } # force capture of interpolated lexical
480 while ( $given =~ m{ \G (?: $op_union )? ($type) }gcx ) {
483 (pos($given) eq length($given))
484 || Moose->throw_error("'$given' didn't parse (parse-pos="
492 sub _detect_type_constraint_union {
493 { no warnings 'void'; $any; } # force capture of interpolated lexical
494 $_[0] =~ m{^ $type $op_union $type ( $op_union .* )? $}x;
498 ## --------------------------------------------------------
499 # define some basic built-in types
500 ## --------------------------------------------------------
502 # By making these classes immutable before creating all the types we
503 # below, we avoid repeatedly calling the slow MOP-based accessors.
505 inline_constructor => 1,
506 constructor_name => "_new",
508 # these are Class::MOP accessors, so they need inlining
509 inline_accessors => 1
510 ) for grep { $_->is_mutable }
513 Moose::Meta::TypeConstraint
514 Moose::Meta::TypeConstraint::Union
515 Moose::Meta::TypeConstraint::Parameterized
516 Moose::Meta::TypeConstraint::Parameterizable
517 Moose::Meta::TypeConstraint::Class
518 Moose::Meta::TypeConstraint::Role
519 Moose::Meta::TypeConstraint::Enum
520 Moose::Meta::TypeConstraint::Registry
523 type 'Any' => where { 1 }; # meta-type including all
524 type 'Item' => where { 1 }; # base-type
526 subtype 'Undef' => as 'Item' => where { !defined($_) };
527 subtype 'Defined' => as 'Item' => where { defined($_) };
531 => where { !defined($_) || $_ eq "" || "$_" eq '1' || "$_" eq '0' };
535 => where { !ref($_) }
536 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Value;
541 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Ref;
546 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Str;
550 => where { Scalar::Util::looks_like_number($_) }
551 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Num;
555 => where { "$_" =~ /^-?[0-9]+$/ }
556 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Int;
558 subtype 'ScalarRef' => as 'Ref' => where { ref($_) eq 'SCALAR' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ScalarRef;
559 subtype 'CodeRef' => as 'Ref' => where { ref($_) eq 'CODE' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::CodeRef;
560 subtype 'RegexpRef' => as 'Ref' => where { ref($_) eq 'Regexp' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::RegexpRef;
561 subtype 'GlobRef' => as 'Ref' => where { ref($_) eq 'GLOB' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::GlobRef;
564 # scalar filehandles are GLOB refs,
565 # but a GLOB ref is not always a filehandle
568 => where { Scalar::Util::openhandle($_) || ( blessed($_) && $_->isa("IO::Handle") ) }
569 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::FileHandle;
572 # blessed(qr/.../) returns true,.. how odd
575 => where { blessed($_) && blessed($_) ne 'Regexp' }
576 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Object;
580 => where { $_->can('does') }
581 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Role;
583 my $_class_name_checker = sub {
588 => where { Class::MOP::is_class_loaded($_) }
589 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ClassName;
591 ## --------------------------------------------------------
592 # parameterizable types ...
594 $REGISTRY->add_type_constraint(
595 Moose::Meta::TypeConstraint::Parameterizable->new(
597 package_defined_in => __PACKAGE__,
598 parent => find_type_constraint('Ref'),
599 constraint => sub { ref($_) eq 'ARRAY' },
600 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::ArrayRef,
601 constraint_generator => sub {
602 my $type_parameter = shift;
603 my $check = $type_parameter->_compiled_type_constraint;
605 foreach my $x (@$_) {
606 ($check->($x)) || return
613 $REGISTRY->add_type_constraint(
614 Moose::Meta::TypeConstraint::Parameterizable->new(
616 package_defined_in => __PACKAGE__,
617 parent => find_type_constraint('Ref'),
618 constraint => sub { ref($_) eq 'HASH' },
619 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::HashRef,
620 constraint_generator => sub {
621 my $type_parameter = shift;
622 my $check = $type_parameter->_compiled_type_constraint;
624 foreach my $x (values %$_) {
625 ($check->($x)) || return
632 $REGISTRY->add_type_constraint(
633 Moose::Meta::TypeConstraint::Parameterizable->new(
635 package_defined_in => __PACKAGE__,
636 parent => find_type_constraint('Item'),
637 constraint => sub { 1 },
638 constraint_generator => sub {
639 my $type_parameter = shift;
640 my $check = $type_parameter->_compiled_type_constraint;
642 return 1 if not(defined($_)) || $check->($_);
649 my @PARAMETERIZABLE_TYPES = map {
650 $REGISTRY->get_type_constraint($_)
651 } qw[ArrayRef HashRef Maybe];
653 sub get_all_parameterizable_types { @PARAMETERIZABLE_TYPES }
654 sub add_parameterizable_type {
656 (blessed $type && $type->isa('Moose::Meta::TypeConstraint::Parameterizable'))
657 || Moose->throw_error("Type must be a Moose::Meta::TypeConstraint::Parameterizable not $type");
658 push @PARAMETERIZABLE_TYPES => $type;
661 ## --------------------------------------------------------
662 # end of built-in types ...
663 ## --------------------------------------------------------
666 my @BUILTINS = list_all_type_constraints();
667 sub list_all_builtin_type_constraints { @BUILTINS }
678 Moose::Util::TypeConstraints - Type constraint system for Moose
682 use Moose::Util::TypeConstraints;
684 type 'Num' => where { Scalar::Util::looks_like_number($_) };
690 subtype 'NaturalLessThanTen'
693 => message { "This number ($_) is not less than ten!" };
699 enum 'RGBColors' => qw(red green blue);
703 This module provides Moose with the ability to create custom type
704 contraints to be used in attribute definition.
706 =head2 Important Caveat
708 This is B<NOT> a type system for Perl 5. These are type constraints,
709 and they are not used by Moose unless you tell it to. No type
710 inference is performed, expression are not typed, etc. etc. etc.
712 This is simply a means of creating small constraint functions which
713 can be used to simplify your own type-checking code, with the added
714 side benefit of making your intentions clearer through self-documentation.
716 =head2 Slightly Less Important Caveat
718 It is B<always> a good idea to quote your type and subtype names.
720 This is to prevent perl from trying to execute the call as an indirect
721 object call. This issue only seems to come up when you have a subtype
722 the same name as a valid class, but when the issue does arise it tends
723 to be quite annoying to debug.
725 So for instance, this:
727 subtype DateTime => as Object => where { $_->isa('DateTime') };
729 will I<Just Work>, while this:
732 subtype DateTime => as Object => where { $_->isa('DateTime') };
734 will fail silently and cause many headaches. The simple way to solve
735 this, as well as future proof your subtypes from classes which have
736 yet to have been created yet, is to simply do this:
739 subtype 'DateTime' => as 'Object' => where { $_->isa('DateTime') };
741 =head2 Default Type Constraints
743 This module also provides a simple hierarchy for Perl 5 types, here is
744 that hierarchy represented visually.
768 B<NOTE:> Any type followed by a type parameter C<[`a]> can be
769 parameterized, this means you can say:
771 ArrayRef[Int] # an array of integers
772 HashRef[CodeRef] # a hash of str to CODE ref mappings
773 Maybe[Str] # value may be a string, may be undefined
775 B<NOTE:> Unless you parameterize a type, then it is invalid to
776 include the square brackets. I.e. C<ArrayRef[]> will be
777 literally interpreted as a type name.
779 B<NOTE:> The C<Undef> type constraint for the most part works
780 correctly now, but edge cases may still exist, please use it
783 B<NOTE:> The C<ClassName> type constraint does a complex package
784 existence check. This means that your class B<must> be loaded for
785 this type constraint to pass. I know this is not ideal for all,
786 but it is a saner restriction than most others.
788 =head2 Type Constraint Naming
790 Since the types created by this module are global, it is suggested
791 that you namespace your types just as you would namespace your
792 modules. So instead of creating a I<Color> type for your B<My::Graphics>
793 module, you would call the type I<My::Graphics::Color> instead.
795 =head2 Use with Other Constraint Modules
797 This module should play fairly nicely with other constraint
798 modules with only some slight tweaking. The C<where> clause
799 in types is expected to be a C<CODE> reference which checks
800 it's first argument and returns a boolean. Since most constraint
801 modules work in a similar way, it should be simple to adapt
802 them to work with Moose.
804 For instance, this is how you could use it with
805 L<Declare::Constraints::Simple> to declare a completely new type.
807 type 'HashOfArrayOfObjects'
810 -values => IsArrayRef( IsObject ));
812 For more examples see the F<t/200_examples/204_example_w_DCS.t>
815 Here is an example of using L<Test::Deep> and it's non-test
816 related C<eq_deeply> function.
818 type 'ArrayOfHashOfBarsAndRandomNumbers'
821 array_each(subhashof({
823 random_number => ignore()
827 For a complete example see the
828 F<t/200_examples/205_example_w_TestDeep.t> test file.
832 =head2 Type Constraint Constructors
834 The following functions are used to create type constraints.
835 They will then register the type constraints in a global store
836 where Moose can get to them if it needs to.
838 See the L<SYNOPSIS> for an example of how to use these.
842 =item B<type ($name, $where_clause)>
844 This creates a base type, which has no parent.
846 =item B<subtype ($name, $parent, $where_clause, ?$message)>
848 This creates a named subtype.
850 =item B<subtype ($parent, $where_clause, ?$message)>
852 This creates an unnamed subtype and will return the type
853 constraint meta-object, which will be an instance of
854 L<Moose::Meta::TypeConstraint>.
856 =item B<class_type ($class, ?$options)>
858 Creates a type constraint with the name C<$class> and the metaclass
859 L<Moose::Meta::TypeConstraint::Class>.
861 =item B<role_type ($role, ?$options)>
863 Creates a type constraint with the name C<$role> and the metaclass
864 L<Moose::Meta::TypeConstraint::Role>.
866 =item B<maybe_type ($type)>
868 Creates a type constraint for either C<undef> or something of the
871 =item B<enum ($name, @values)>
873 This will create a basic subtype for a given set of strings.
874 The resulting constraint will be a subtype of C<Str> and
875 will match any of the items in C<@values>. It is case sensitive.
876 See the L<SYNOPSIS> for a simple example.
878 B<NOTE:> This is not a true proper enum type, it is simple
879 a convient constraint builder.
881 =item B<enum (\@values)>
883 If passed an ARRAY reference instead of the C<$name>, C<@values> pair,
884 this will create an unnamed enum. This can then be used in an attribute
887 has 'sort_order' => (
889 isa => enum([qw[ ascending descending ]]),
894 This is just sugar for the type constraint construction syntax.
898 This is just sugar for the type constraint construction syntax.
900 Takes a block/code ref as an argument. When the type constraint is
901 tested, the supplied code is run with the value to be tested in
902 $_. This block should return true or false to indicate whether or not
903 the constraint check passed.
907 This is just sugar for the type constraint construction syntax.
909 Takes a block/code ref as an argument. When the type constraint fails,
910 then the code block is run (with the value provided in $_). This code
911 ref should return a string, which will be used in the text of the
916 This can be used to define a "hand optimized" version of your
917 type constraint which can be used to avoid traversing a subtype
918 constraint heirarchy.
920 B<NOTE:> You should only use this if you know what you are doing,
921 all the built in types use this, so your subtypes (assuming they
922 are shallow) will not likely need to use this.
926 =head2 Type Coercion Constructors
928 Type constraints can also contain type coercions as well. If you
929 ask your accessor to coerce, then Moose will run the type-coercion
930 code first, followed by the type constraint check. This feature
931 should be used carefully as it is very powerful and could easily
932 take off a limb if you are not careful.
934 See the L<SYNOPSIS> for an example of how to use these.
942 This is just sugar for the type coercion construction syntax.
946 This is just sugar for the type coercion construction syntax.
950 =head2 Type Constraint Construction & Locating
954 =item B<normalize_type_constraint_name ($type_constraint_name)>
956 Given a string that is expected to match a type constraint, will normalize the
957 string so that extra whitespace and newlines are removed.
959 =item B<create_type_constraint_union ($pipe_seperated_types | @type_constraint_names)>
961 Given string with C<$pipe_seperated_types> or a list of C<@type_constraint_names>,
962 this will return a L<Moose::Meta::TypeConstraint::Union> instance.
964 =item B<create_parameterized_type_constraint ($type_name)>
966 Given a C<$type_name> in the form of:
968 BaseType[ContainerType]
970 this will extract the base type and container type and build an instance of
971 L<Moose::Meta::TypeConstraint::Parameterized> for it.
973 =item B<create_class_type_constraint ($class, ?$options)>
975 Given a class name it will create a new L<Moose::Meta::TypeConstraint::Class>
976 object for that class name.
978 =item B<create_role_type_constraint ($role, ?$options)>
980 Given a role name it will create a new L<Moose::Meta::TypeConstraint::Role>
981 object for that role name.
983 =item B<create_enum_type_constraint ($name, $values)>
985 =item B<find_or_parse_type_constraint ($type_name)>
987 This will attempt to find or create a type constraint given the a C<$type_name>.
988 If it cannot find it in the registry, it will see if it should be a union or
989 container type an create one if appropriate
991 =item B<find_or_create_type_constraint ($type_name, ?$options_for_anon_type)>
993 This function will first call C<find_or_parse_type_constraint> with the type name.
995 If no type is found or created, but C<$options_for_anon_type> are provided, it
996 will create the corresponding type.
998 This was used by the C<does> and C<isa> parameters to L<Moose::Meta::Attribute>
999 and are now superseded by C<find_or_create_isa_type_constraint> and
1000 C<find_or_create_does_type_constraint>.
1002 =item B<find_or_create_isa_type_constraint ($type_name)>
1004 =item B<find_or_create_does_type_constraint ($type_name)>
1006 Attempts to parse the type name using C<find_or_parse_type_constraint> and if
1007 no appropriate constraint is found will create a new anonymous one.
1009 The C<isa> variant will use C<create_class_type_constraint> and the C<does>
1010 variant will use C<create_role_type_constraint>.
1012 =item B<find_type_constraint ($type_name)>
1014 This function can be used to locate a specific type constraint
1015 meta-object, of the class L<Moose::Meta::TypeConstraint> or a
1016 derivative. What you do with it from there is up to you :)
1018 =item B<register_type_constraint ($type_object)>
1020 This function will register a named type constraint with the type registry.
1022 =item B<get_type_constraint_registry>
1024 Fetch the L<Moose::Meta::TypeConstraint::Registry> object which
1025 keeps track of all type constraints.
1027 =item B<list_all_type_constraints>
1029 This will return a list of type constraint names, you can then
1030 fetch them using C<find_type_constraint ($type_name)> if you
1033 =item B<list_all_builtin_type_constraints>
1035 This will return a list of builtin type constraints, meaning,
1036 those which are defined in this module. See the section
1037 labeled L<Default Type Constraints> for a complete list.
1039 =item B<export_type_constraints_as_functions>
1041 This will export all the current type constraints as functions
1042 into the caller's namespace. Right now, this is mostly used for
1043 testing, but it might prove useful to others.
1045 =item B<get_all_parameterizable_types>
1047 This returns all the parameterizable types that have been registered.
1049 =item B<add_parameterizable_type ($type)>
1051 Adds C<$type> to the list of parameterizable types
1055 =head2 Namespace Management
1061 This will remove all the type constraint keywords from the
1062 calling class namespace.
1068 All complex software has bugs lurking in it, and this module is no
1069 exception. If you find a bug please either email me, or add the bug
1074 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1076 =head1 COPYRIGHT AND LICENSE
1078 Copyright 2006-2008 by Infinity Interactive, Inc.
1080 L<http://www.iinteractive.com>
1082 This library is free software; you can redistribute it and/or modify
1083 it under the same terms as Perl itself.