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 || __PACKAGE__->_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 __PACKAGE__->_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 || __PACKAGE__->_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 __PACKAGE__->_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 # || __PACKAGE__->_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 # || __PACKAGE__->_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 __PACKAGE__->_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 || __PACKAGE__->_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 || __PACKAGE__->_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 || __PACKAGE__->_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 || __PACKAGE__->_throw_error("Type must be a Moose::Meta::TypeConstraint::Parameterizable not $type");
649 push @PARAMETERIZABLE_TYPES => $type;
652 ## --------------------------------------------------------
653 # end of built-in types ...
654 ## --------------------------------------------------------
657 my @BUILTINS = list_all_type_constraints();
658 sub list_all_builtin_type_constraints { @BUILTINS }
664 goto &Moose::throw_error;
675 Moose::Util::TypeConstraints - Type constraint system for Moose
679 use Moose::Util::TypeConstraints;
681 type 'Num' => where { Scalar::Util::looks_like_number($_) };
687 subtype 'NaturalLessThanTen'
690 => message { "This number ($_) is not less than ten!" };
696 enum 'RGBColors' => qw(red green blue);
700 This module provides Moose with the ability to create custom type
701 contraints to be used in attribute definition.
703 =head2 Important Caveat
705 This is B<NOT> a type system for Perl 5. These are type constraints,
706 and they are not used by Moose unless you tell it to. No type
707 inference is performed, expression are not typed, etc. etc. etc.
709 This is simply a means of creating small constraint functions which
710 can be used to simplify your own type-checking code, with the added
711 side benefit of making your intentions clearer through self-documentation.
713 =head2 Slightly Less Important Caveat
715 It is B<always> a good idea to quote your type and subtype names.
717 This is to prevent perl from trying to execute the call as an indirect
718 object call. This issue only seems to come up when you have a subtype
719 the same name as a valid class, but when the issue does arise it tends
720 to be quite annoying to debug.
722 So for instance, this:
724 subtype DateTime => as Object => where { $_->isa('DateTime') };
726 will I<Just Work>, while this:
729 subtype DateTime => as Object => where { $_->isa('DateTime') };
731 will fail silently and cause many headaches. The simple way to solve
732 this, as well as future proof your subtypes from classes which have
733 yet to have been created yet, is to simply do this:
736 subtype 'DateTime' => as 'Object' => where { $_->isa('DateTime') };
738 =head2 Default Type Constraints
740 This module also provides a simple hierarchy for Perl 5 types, here is
741 that hierarchy represented visually.
765 B<NOTE:> Any type followed by a type parameter C<[`a]> can be
766 parameterized, this means you can say:
768 ArrayRef[Int] # an array of integers
769 HashRef[CodeRef] # a hash of str to CODE ref mappings
770 Maybe[Str] # value may be a string, may be undefined
772 If Moose finds a name in brackets that it does not recognize as an
773 existing type, it assumes that this is a class name, for example
774 C<ArrayRef[DateTime]>.
776 B<NOTE:> Unless you parameterize a type, then it is invalid to
777 include the square brackets. I.e. C<ArrayRef[]> will be
778 literally interpreted as a type name.
780 B<NOTE:> The C<Undef> type constraint for the most part works
781 correctly now, but edge cases may still exist, please use it
784 B<NOTE:> The C<ClassName> type constraint does a complex package
785 existence check. This means that your class B<must> be loaded for
786 this type constraint to pass. I know this is not ideal for all,
787 but it is a saner restriction than most others.
789 =head2 Type Constraint Naming
791 Since the types created by this module are global, it is suggested
792 that you namespace your types just as you would namespace your
793 modules. So instead of creating a I<Color> type for your B<My::Graphics>
794 module, you would call the type I<My.Graphics.Color> instead.
796 =head2 Use with Other Constraint Modules
798 This module should play fairly nicely with other constraint
799 modules with only some slight tweaking. The C<where> clause
800 in types is expected to be a C<CODE> reference which checks
801 it's first argument and returns a boolean. Since most constraint
802 modules work in a similar way, it should be simple to adapt
803 them to work with Moose.
805 For instance, this is how you could use it with
806 L<Declare::Constraints::Simple> to declare a completely new type.
808 type 'HashOfArrayOfObjects'
811 -values => IsArrayRef( IsObject ));
813 For more examples see the F<t/200_examples/204_example_w_DCS.t>
816 Here is an example of using L<Test::Deep> and it's non-test
817 related C<eq_deeply> function.
819 type 'ArrayOfHashOfBarsAndRandomNumbers'
822 array_each(subhashof({
824 random_number => ignore()
828 For a complete example see the
829 F<t/200_examples/205_example_w_TestDeep.t> test file.
833 =head2 Type Constraint Constructors
835 The following functions are used to create type constraints.
836 They will then register the type constraints in a global store
837 where Moose can get to them if it needs to.
839 See the L<SYNOPSIS> for an example of how to use these.
843 =item B<type ($name, $where_clause)>
845 This creates a base type, which has no parent.
847 =item B<subtype ($name, $parent, $where_clause, ?$message)>
849 This creates a named subtype.
851 If you provide a parent that Moose does not recognize, it will
852 automatically create a new class type constraint for this name.
854 =item B<subtype ($parent, $where_clause, ?$message)>
856 This creates an unnamed subtype and will return the type
857 constraint meta-object, which will be an instance of
858 L<Moose::Meta::TypeConstraint>.
860 =item B<class_type ($class, ?$options)>
862 Creates a type constraint with the name C<$class> and the metaclass
863 L<Moose::Meta::TypeConstraint::Class>.
865 =item B<role_type ($role, ?$options)>
867 Creates a type constraint with the name C<$role> and the metaclass
868 L<Moose::Meta::TypeConstraint::Role>.
870 =item B<maybe_type ($type)>
872 Creates a type constraint for either C<undef> or something of the
875 =item B<enum ($name, @values)>
877 This will create a basic subtype for a given set of strings.
878 The resulting constraint will be a subtype of C<Str> and
879 will match any of the items in C<@values>. It is case sensitive.
880 See the L<SYNOPSIS> for a simple example.
882 B<NOTE:> This is not a true proper enum type, it is simple
883 a convient constraint builder.
885 =item B<enum (\@values)>
887 If passed an ARRAY reference instead of the C<$name>, C<@values> pair,
888 this will create an unnamed enum. This can then be used in an attribute
891 has 'sort_order' => (
893 isa => enum([qw[ ascending descending ]]),
898 This is just sugar for the type constraint construction syntax.
902 This is just sugar for the type constraint construction syntax.
904 Takes a block/code ref as an argument. When the type constraint is
905 tested, the supplied code is run with the value to be tested in
906 $_. This block should return true or false to indicate whether or not
907 the constraint check passed.
911 This is just sugar for the type constraint construction syntax.
913 Takes a block/code ref as an argument. When the type constraint fails,
914 then the code block is run (with the value provided in $_). This code
915 ref should return a string, which will be used in the text of the
920 This can be used to define a "hand optimized" version of your
921 type constraint which can be used to avoid traversing a subtype
922 constraint heirarchy.
924 B<NOTE:> You should only use this if you know what you are doing,
925 all the built in types use this, so your subtypes (assuming they
926 are shallow) will not likely need to use this.
930 =head2 Type Coercion Constructors
932 Type constraints can also contain type coercions as well. If you
933 ask your accessor to coerce, then Moose will run the type-coercion
934 code first, followed by the type constraint check. This feature
935 should be used carefully as it is very powerful and could easily
936 take off a limb if you are not careful.
938 See the L<SYNOPSIS> for an example of how to use these.
946 This is just sugar for the type coercion construction syntax.
950 This is just sugar for the type coercion construction syntax.
954 =head2 Type Constraint Construction & Locating
958 =item B<normalize_type_constraint_name ($type_constraint_name)>
960 Given a string that is expected to match a type constraint, will normalize the
961 string so that extra whitespace and newlines are removed.
963 =item B<create_type_constraint_union ($pipe_seperated_types | @type_constraint_names)>
965 Given string with C<$pipe_seperated_types> or a list of C<@type_constraint_names>,
966 this will return a L<Moose::Meta::TypeConstraint::Union> instance.
968 =item B<create_parameterized_type_constraint ($type_name)>
970 Given a C<$type_name> in the form of:
972 BaseType[ContainerType]
974 this will extract the base type and container type and build an instance of
975 L<Moose::Meta::TypeConstraint::Parameterized> for it.
977 =item B<create_class_type_constraint ($class, ?$options)>
979 Given a class name it will create a new L<Moose::Meta::TypeConstraint::Class>
980 object for that class name.
982 =item B<create_role_type_constraint ($role, ?$options)>
984 Given a role name it will create a new L<Moose::Meta::TypeConstraint::Role>
985 object for that role name.
987 =item B<create_enum_type_constraint ($name, $values)>
989 =item B<find_or_parse_type_constraint ($type_name)>
991 This will attempt to find or create a type constraint given the a C<$type_name>.
992 If it cannot find it in the registry, it will see if it should be a union or
993 container type an create one if appropriate
995 =item B<find_or_create_type_constraint ($type_name, ?$options_for_anon_type)>
997 This function will first call C<find_or_parse_type_constraint> with the type name.
999 If no type is found or created, but C<$options_for_anon_type> are provided, it
1000 will create the corresponding type.
1002 This was used by the C<does> and C<isa> parameters to L<Moose::Meta::Attribute>
1003 and are now superseded by C<find_or_create_isa_type_constraint> and
1004 C<find_or_create_does_type_constraint>.
1006 =item B<find_or_create_isa_type_constraint ($type_name)>
1008 =item B<find_or_create_does_type_constraint ($type_name)>
1010 Attempts to parse the type name using C<find_or_parse_type_constraint> and if
1011 no appropriate constraint is found will create a new anonymous one.
1013 The C<isa> variant will use C<create_class_type_constraint> and the C<does>
1014 variant will use C<create_role_type_constraint>.
1016 =item B<find_type_constraint ($type_name)>
1018 This function can be used to locate a specific type constraint
1019 meta-object, of the class L<Moose::Meta::TypeConstraint> or a
1020 derivative. What you do with it from there is up to you :)
1022 =item B<register_type_constraint ($type_object)>
1024 This function will register a named type constraint with the type registry.
1026 =item B<get_type_constraint_registry>
1028 Fetch the L<Moose::Meta::TypeConstraint::Registry> object which
1029 keeps track of all type constraints.
1031 =item B<list_all_type_constraints>
1033 This will return a list of type constraint names, you can then
1034 fetch them using C<find_type_constraint ($type_name)> if you
1037 =item B<list_all_builtin_type_constraints>
1039 This will return a list of builtin type constraints, meaning,
1040 those which are defined in this module. See the section
1041 labeled L<Default Type Constraints> for a complete list.
1043 =item B<export_type_constraints_as_functions>
1045 This will export all the current type constraints as functions
1046 into the caller's namespace. Right now, this is mostly used for
1047 testing, but it might prove useful to others.
1049 =item B<get_all_parameterizable_types>
1051 This returns all the parameterizable types that have been registered.
1053 =item B<add_parameterizable_type ($type)>
1055 Adds C<$type> to the list of parameterizable types
1059 =head2 Namespace Management
1065 This will remove all the type constraint keywords from the
1066 calling class namespace.
1072 All complex software has bugs lurking in it, and this module is no
1073 exception. If you find a bug please either email me, or add the bug
1078 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1080 =head1 COPYRIGHT AND LICENSE
1082 Copyright 2006-2008 by Infinity Interactive, Inc.
1084 L<http://www.iinteractive.com>
1086 This library is free software; you can redistribute it and/or modify
1087 it under the same terms as Perl itself.