2 package Moose::Util::TypeConstraints;
8 use List::MoreUtils qw( all );
9 use Scalar::Util 'blessed';
12 our $VERSION = '0.65';
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')->parameterize($type_parameter)
314 my ($type_name, @coercion_map) = @_;
315 _install_type_coercions($type_name, \@coercion_map);
320 sub where (&) { $_[0] }
321 sub via (&) { $_[0] }
323 sub message (&) { +{ message => $_[0] } }
324 sub optimize_as (&) { +{ optimized => $_[0] } }
327 my ($type_name, @values) = @_;
329 # if only an array-ref is passed then
330 # you get an anon-enum
332 if (ref $type_name eq 'ARRAY' && !@values) {
333 @values = @$type_name;
336 (scalar @values >= 2)
337 || Moose->throw_error("You must have at least two values to enumerate through");
338 my %valid = map { $_ => 1 } @values;
340 register_type_constraint(
341 create_enum_type_constraint(
348 sub create_enum_type_constraint {
349 my ( $type_name, $values ) = @_;
351 Moose::Meta::TypeConstraint::Enum->new(
352 name => $type_name || '__ANON__',
357 ## --------------------------------------------------------
358 ## desugaring functions ...
359 ## --------------------------------------------------------
361 sub _create_type_constraint ($$$;$$) {
366 my ( $message, $optimized );
368 $message = $_->{message} if exists $_->{message};
369 $optimized = $_->{optimized} if exists $_->{optimized};
372 my $pkg_defined_in = scalar( caller(0) );
374 if ( defined $name ) {
375 my $type = $REGISTRY->get_type_constraint($name);
377 ( $type->_package_defined_in eq $pkg_defined_in )
379 "The type constraint '$name' has already been created in "
380 . $type->_package_defined_in
381 . " and cannot be created again in "
388 package_defined_in => $pkg_defined_in,
390 ( $check ? ( constraint => $check ) : () ),
391 ( $message ? ( message => $message ) : () ),
392 ( $optimized ? ( optimized => $optimized ) : () ),
398 = blessed $parent ? $parent : find_or_create_isa_type_constraint($parent) )
400 $constraint = $parent->create_child_type(%opts);
403 $constraint = Moose::Meta::TypeConstraint->new(%opts);
406 $REGISTRY->add_type_constraint($constraint)
412 sub _install_type_coercions ($$) {
413 my ($type_name, $coercion_map) = @_;
414 my $type = find_type_constraint($type_name);
416 || Moose->throw_error("Cannot find type '$type_name', perhaps you forgot to load it.");
417 if ($type->has_coercion) {
418 $type->coercion->add_type_coercions(@$coercion_map);
421 my $type_coercion = Moose::Meta::TypeCoercion->new(
422 type_coercion_map => $coercion_map,
423 type_constraint => $type
425 $type->coercion($type_coercion);
429 ## --------------------------------------------------------
430 ## type notation parsing ...
431 ## --------------------------------------------------------
434 # All I have to say is mugwump++ cause I know
435 # do not even have enough regexp-fu to be able
436 # to have written this (I can only barely
437 # understand it as it is)
442 my $valid_chars = qr{[\w:]};
443 my $type_atom = qr{ $valid_chars+ };
447 my $type = qr{ $valid_chars+ (?: \[ \s* (??{$any}) \s* \] )? }x;
448 my $type_capture_parts = qr{ ($valid_chars+) (?: \[ \s* ((??{$any})) \s* \] )? }x;
449 my $type_with_parameter = qr{ $valid_chars+ \[ \s* (??{$any}) \s* \] }x;
451 my $op_union = qr{ \s* \| \s* }x;
452 my $union = qr{ $type (?: $op_union $type )+ }x;
454 $any = qr{ $type | $union }x;
456 sub _parse_parameterized_type_constraint {
457 { no warnings 'void'; $any; } # force capture of interpolated lexical
458 $_[0] =~ m{ $type_capture_parts }x;
462 sub _detect_parameterized_type_constraint {
463 { no warnings 'void'; $any; } # force capture of interpolated lexical
464 $_[0] =~ m{ ^ $type_with_parameter $ }x;
467 sub _parse_type_constraint_union {
468 { no warnings 'void'; $any; } # force capture of interpolated lexical
471 while ( $given =~ m{ \G (?: $op_union )? ($type) }gcx ) {
474 (pos($given) eq length($given))
475 || Moose->throw_error("'$given' didn't parse (parse-pos="
483 sub _detect_type_constraint_union {
484 { no warnings 'void'; $any; } # force capture of interpolated lexical
485 $_[0] =~ m{^ $type $op_union $type ( $op_union .* )? $}x;
489 ## --------------------------------------------------------
490 # define some basic built-in types
491 ## --------------------------------------------------------
493 # By making these classes immutable before creating all the types we
494 # below, we avoid repeatedly calling the slow MOP-based accessors.
496 inline_constructor => 1,
497 constructor_name => "_new",
499 # these are Class::MOP accessors, so they need inlining
500 inline_accessors => 1
501 ) for grep { $_->is_mutable }
504 Moose::Meta::TypeConstraint
505 Moose::Meta::TypeConstraint::Union
506 Moose::Meta::TypeConstraint::Parameterized
507 Moose::Meta::TypeConstraint::Parameterizable
508 Moose::Meta::TypeConstraint::Class
509 Moose::Meta::TypeConstraint::Role
510 Moose::Meta::TypeConstraint::Enum
511 Moose::Meta::TypeConstraint::Registry
514 type 'Any' => where { 1 }; # meta-type including all
515 type 'Item' => where { 1 }; # base-type
517 subtype 'Undef' => as 'Item' => where { !defined($_) };
518 subtype 'Defined' => as 'Item' => where { defined($_) };
522 => where { !defined($_) || $_ eq "" || "$_" eq '1' || "$_" eq '0' };
526 => where { !ref($_) }
527 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Value;
532 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Ref;
537 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Str;
541 => where { Scalar::Util::looks_like_number($_) }
542 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Num;
546 => where { "$_" =~ /^-?[0-9]+$/ }
547 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Int;
549 subtype 'ScalarRef' => as 'Ref' => where { ref($_) eq 'SCALAR' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ScalarRef;
550 subtype 'CodeRef' => as 'Ref' => where { ref($_) eq 'CODE' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::CodeRef;
551 subtype 'RegexpRef' => as 'Ref' => where { ref($_) eq 'Regexp' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::RegexpRef;
552 subtype 'GlobRef' => as 'Ref' => where { ref($_) eq 'GLOB' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::GlobRef;
555 # scalar filehandles are GLOB refs,
556 # but a GLOB ref is not always a filehandle
559 => where { Scalar::Util::openhandle($_) || ( blessed($_) && $_->isa("IO::Handle") ) }
560 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::FileHandle;
563 # blessed(qr/.../) returns true,.. how odd
566 => where { blessed($_) && blessed($_) ne 'Regexp' }
567 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Object;
571 => where { $_->can('does') }
572 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Role;
574 my $_class_name_checker = sub {
579 => where { Class::MOP::is_class_loaded($_) }
580 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ClassName;
582 ## --------------------------------------------------------
583 # parameterizable types ...
585 $REGISTRY->add_type_constraint(
586 Moose::Meta::TypeConstraint::Parameterizable->new(
588 package_defined_in => __PACKAGE__,
589 parent => find_type_constraint('Ref'),
590 constraint => sub { ref($_) eq 'ARRAY' },
591 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::ArrayRef,
592 constraint_generator => sub {
593 my $type_parameter = shift;
594 my $check = $type_parameter->_compiled_type_constraint;
596 foreach my $x (@$_) {
597 ($check->($x)) || return
604 $REGISTRY->add_type_constraint(
605 Moose::Meta::TypeConstraint::Parameterizable->new(
607 package_defined_in => __PACKAGE__,
608 parent => find_type_constraint('Ref'),
609 constraint => sub { ref($_) eq 'HASH' },
610 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::HashRef,
611 constraint_generator => sub {
612 my $type_parameter = shift;
613 my $check = $type_parameter->_compiled_type_constraint;
615 foreach my $x (values %$_) {
616 ($check->($x)) || return
623 $REGISTRY->add_type_constraint(
624 Moose::Meta::TypeConstraint::Parameterizable->new(
626 package_defined_in => __PACKAGE__,
627 parent => find_type_constraint('Item'),
628 constraint => sub { 1 },
629 constraint_generator => sub {
630 my $type_parameter = shift;
631 my $check = $type_parameter->_compiled_type_constraint;
633 return 1 if not(defined($_)) || $check->($_);
640 my @PARAMETERIZABLE_TYPES = map {
641 $REGISTRY->get_type_constraint($_)
642 } qw[ArrayRef HashRef Maybe];
644 sub get_all_parameterizable_types { @PARAMETERIZABLE_TYPES }
645 sub add_parameterizable_type {
647 (blessed $type && $type->isa('Moose::Meta::TypeConstraint::Parameterizable'))
648 || Moose->throw_error("Type must be a Moose::Meta::TypeConstraint::Parameterizable not $type");
649 push @PARAMETERIZABLE_TYPES => $type;
652 ## --------------------------------------------------------
653 # end of built-in types ...
654 ## --------------------------------------------------------
657 my @BUILTINS = list_all_type_constraints();
658 sub list_all_builtin_type_constraints { @BUILTINS }
669 Moose::Util::TypeConstraints - Type constraint system for Moose
673 use Moose::Util::TypeConstraints;
675 type 'Num' => where { Scalar::Util::looks_like_number($_) };
681 subtype 'NaturalLessThanTen'
684 => message { "This number ($_) is not less than ten!" };
690 enum 'RGBColors' => qw(red green blue);
694 This module provides Moose with the ability to create custom type
695 contraints to be used in attribute definition.
697 =head2 Important Caveat
699 This is B<NOT> a type system for Perl 5. These are type constraints,
700 and they are not used by Moose unless you tell it to. No type
701 inference is performed, expression are not typed, etc. etc. etc.
703 This is simply a means of creating small constraint functions which
704 can be used to simplify your own type-checking code, with the added
705 side benefit of making your intentions clearer through self-documentation.
707 =head2 Slightly Less Important Caveat
709 It is B<always> a good idea to quote your type and subtype names.
711 This is to prevent perl from trying to execute the call as an indirect
712 object call. This issue only seems to come up when you have a subtype
713 the same name as a valid class, but when the issue does arise it tends
714 to be quite annoying to debug.
716 So for instance, this:
718 subtype DateTime => as Object => where { $_->isa('DateTime') };
720 will I<Just Work>, while this:
723 subtype DateTime => as Object => where { $_->isa('DateTime') };
725 will fail silently and cause many headaches. The simple way to solve
726 this, as well as future proof your subtypes from classes which have
727 yet to have been created yet, is to simply do this:
730 subtype 'DateTime' => as 'Object' => where { $_->isa('DateTime') };
732 =head2 Default Type Constraints
734 This module also provides a simple hierarchy for Perl 5 types, here is
735 that hierarchy represented visually.
759 B<NOTE:> Any type followed by a type parameter C<[`a]> can be
760 parameterized, this means you can say:
762 ArrayRef[Int] # an array of integers
763 HashRef[CodeRef] # a hash of str to CODE ref mappings
764 Maybe[Str] # value may be a string, may be undefined
766 If Moose finds a name in brackets that it does not recognize as an
767 existing type, it assumes that this is a class name, for example
768 C<ArrayRef[DateTime]>.
770 B<NOTE:> Unless you parameterize a type, then it is invalid to
771 include the square brackets. I.e. C<ArrayRef[]> will be
772 literally interpreted as a type name.
774 B<NOTE:> The C<Undef> type constraint for the most part works
775 correctly now, but edge cases may still exist, please use it
778 B<NOTE:> The C<ClassName> type constraint does a complex package
779 existence check. This means that your class B<must> be loaded for
780 this type constraint to pass. I know this is not ideal for all,
781 but it is a saner restriction than most others.
783 =head2 Type Constraint Naming
785 Since the types created by this module are global, it is suggested
786 that you namespace your types just as you would namespace your
787 modules. So instead of creating a I<Color> type for your B<My::Graphics>
788 module, you would call the type I<My::Graphics::Color> instead.
790 =head2 Use with Other Constraint Modules
792 This module should play fairly nicely with other constraint
793 modules with only some slight tweaking. The C<where> clause
794 in types is expected to be a C<CODE> reference which checks
795 it's first argument and returns a boolean. Since most constraint
796 modules work in a similar way, it should be simple to adapt
797 them to work with Moose.
799 For instance, this is how you could use it with
800 L<Declare::Constraints::Simple> to declare a completely new type.
802 type 'HashOfArrayOfObjects'
805 -values => IsArrayRef( IsObject ));
807 For more examples see the F<t/200_examples/204_example_w_DCS.t>
810 Here is an example of using L<Test::Deep> and it's non-test
811 related C<eq_deeply> function.
813 type 'ArrayOfHashOfBarsAndRandomNumbers'
816 array_each(subhashof({
818 random_number => ignore()
822 For a complete example see the
823 F<t/200_examples/205_example_w_TestDeep.t> test file.
827 =head2 Type Constraint Constructors
829 The following functions are used to create type constraints.
830 They will then register the type constraints in a global store
831 where Moose can get to them if it needs to.
833 See the L<SYNOPSIS> for an example of how to use these.
837 =item B<type ($name, $where_clause)>
839 This creates a base type, which has no parent.
841 =item B<subtype ($name, $parent, $where_clause, ?$message)>
843 This creates a named subtype.
845 If you provide a parent that Moose does not recognize, it will
846 automatically create a new class type constraint for this name.
848 =item B<subtype ($parent, $where_clause, ?$message)>
850 This creates an unnamed subtype and will return the type
851 constraint meta-object, which will be an instance of
852 L<Moose::Meta::TypeConstraint>.
854 =item B<class_type ($class, ?$options)>
856 Creates a type constraint with the name C<$class> and the metaclass
857 L<Moose::Meta::TypeConstraint::Class>.
859 =item B<role_type ($role, ?$options)>
861 Creates a type constraint with the name C<$role> and the metaclass
862 L<Moose::Meta::TypeConstraint::Role>.
864 =item B<maybe_type ($type)>
866 Creates a type constraint for either C<undef> or something of the
869 =item B<enum ($name, @values)>
871 This will create a basic subtype for a given set of strings.
872 The resulting constraint will be a subtype of C<Str> and
873 will match any of the items in C<@values>. It is case sensitive.
874 See the L<SYNOPSIS> for a simple example.
876 B<NOTE:> This is not a true proper enum type, it is simple
877 a convient constraint builder.
879 =item B<enum (\@values)>
881 If passed an ARRAY reference instead of the C<$name>, C<@values> pair,
882 this will create an unnamed enum. This can then be used in an attribute
885 has 'sort_order' => (
887 isa => enum([qw[ ascending descending ]]),
892 This is just sugar for the type constraint construction syntax.
896 This is just sugar for the type constraint construction syntax.
898 Takes a block/code ref as an argument. When the type constraint is
899 tested, the supplied code is run with the value to be tested in
900 $_. This block should return true or false to indicate whether or not
901 the constraint check passed.
905 This is just sugar for the type constraint construction syntax.
907 Takes a block/code ref as an argument. When the type constraint fails,
908 then the code block is run (with the value provided in $_). This code
909 ref should return a string, which will be used in the text of the
914 This can be used to define a "hand optimized" version of your
915 type constraint which can be used to avoid traversing a subtype
916 constraint heirarchy.
918 B<NOTE:> You should only use this if you know what you are doing,
919 all the built in types use this, so your subtypes (assuming they
920 are shallow) will not likely need to use this.
924 =head2 Type Coercion Constructors
926 Type constraints can also contain type coercions as well. If you
927 ask your accessor to coerce, then Moose will run the type-coercion
928 code first, followed by the type constraint check. This feature
929 should be used carefully as it is very powerful and could easily
930 take off a limb if you are not careful.
932 See the L<SYNOPSIS> for an example of how to use these.
940 This is just sugar for the type coercion construction syntax.
944 This is just sugar for the type coercion construction syntax.
948 =head2 Type Constraint Construction & Locating
952 =item B<normalize_type_constraint_name ($type_constraint_name)>
954 Given a string that is expected to match a type constraint, will normalize the
955 string so that extra whitespace and newlines are removed.
957 =item B<create_type_constraint_union ($pipe_seperated_types | @type_constraint_names)>
959 Given string with C<$pipe_seperated_types> or a list of C<@type_constraint_names>,
960 this will return a L<Moose::Meta::TypeConstraint::Union> instance.
962 =item B<create_parameterized_type_constraint ($type_name)>
964 Given a C<$type_name> in the form of:
966 BaseType[ContainerType]
968 this will extract the base type and container type and build an instance of
969 L<Moose::Meta::TypeConstraint::Parameterized> for it.
971 =item B<create_class_type_constraint ($class, ?$options)>
973 Given a class name it will create a new L<Moose::Meta::TypeConstraint::Class>
974 object for that class name.
976 =item B<create_role_type_constraint ($role, ?$options)>
978 Given a role name it will create a new L<Moose::Meta::TypeConstraint::Role>
979 object for that role name.
981 =item B<create_enum_type_constraint ($name, $values)>
983 =item B<find_or_parse_type_constraint ($type_name)>
985 This will attempt to find or create a type constraint given the a C<$type_name>.
986 If it cannot find it in the registry, it will see if it should be a union or
987 container type an create one if appropriate
989 =item B<find_or_create_type_constraint ($type_name, ?$options_for_anon_type)>
991 This function will first call C<find_or_parse_type_constraint> with the type name.
993 If no type is found or created, but C<$options_for_anon_type> are provided, it
994 will create the corresponding type.
996 This was used by the C<does> and C<isa> parameters to L<Moose::Meta::Attribute>
997 and are now superseded by C<find_or_create_isa_type_constraint> and
998 C<find_or_create_does_type_constraint>.
1000 =item B<find_or_create_isa_type_constraint ($type_name)>
1002 =item B<find_or_create_does_type_constraint ($type_name)>
1004 Attempts to parse the type name using C<find_or_parse_type_constraint> and if
1005 no appropriate constraint is found will create a new anonymous one.
1007 The C<isa> variant will use C<create_class_type_constraint> and the C<does>
1008 variant will use C<create_role_type_constraint>.
1010 =item B<find_type_constraint ($type_name)>
1012 This function can be used to locate a specific type constraint
1013 meta-object, of the class L<Moose::Meta::TypeConstraint> or a
1014 derivative. What you do with it from there is up to you :)
1016 =item B<register_type_constraint ($type_object)>
1018 This function will register a named type constraint with the type registry.
1020 =item B<get_type_constraint_registry>
1022 Fetch the L<Moose::Meta::TypeConstraint::Registry> object which
1023 keeps track of all type constraints.
1025 =item B<list_all_type_constraints>
1027 This will return a list of type constraint names, you can then
1028 fetch them using C<find_type_constraint ($type_name)> if you
1031 =item B<list_all_builtin_type_constraints>
1033 This will return a list of builtin type constraints, meaning,
1034 those which are defined in this module. See the section
1035 labeled L<Default Type Constraints> for a complete list.
1037 =item B<export_type_constraints_as_functions>
1039 This will export all the current type constraints as functions
1040 into the caller's namespace. Right now, this is mostly used for
1041 testing, but it might prove useful to others.
1043 =item B<get_all_parameterizable_types>
1045 This returns all the parameterizable types that have been registered.
1047 =item B<add_parameterizable_type ($type)>
1049 Adds C<$type> to the list of parameterizable types
1053 =head2 Namespace Management
1059 This will remove all the type constraint keywords from the
1060 calling class namespace.
1066 All complex software has bugs lurking in it, and this module is no
1067 exception. If you find a bug please either email me, or add the bug
1072 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1074 =head1 COPYRIGHT AND LICENSE
1076 Copyright 2006-2008 by Infinity Interactive, Inc.
1078 L<http://www.iinteractive.com>
1080 This library is free software; you can redistribute it and/or modify
1081 it under the same terms as Perl itself.