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, $type_parameter) = _parse_parameterized_type_constraint($type_constraint_name);
122 (defined $base_type && defined $type_parameter)
123 || Moose->throw_error("Could not parse type name ($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 ) = @_;
138 if ( $base_type_tc->can('parameterize') ) {
139 return $base_type_tc->parameterize($type_parameter);
142 return Moose::Meta::TypeConstraint::Parameterized->new(
143 name => $base_type_tc->name . '[' . $type_parameter . ']',
144 parent => $base_type_tc,
146 find_or_create_isa_type_constraint($type_parameter),
151 #should we also support optimized checks?
152 sub create_class_type_constraint ($;$) {
153 my ( $class, $options ) = @_;
155 # too early for this check
156 #find_type_constraint("ClassName")->check($class)
157 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
165 $options{name} ||= "__ANON__";
167 Moose::Meta::TypeConstraint::Class->new( %options );
170 sub create_role_type_constraint ($;$) {
171 my ( $role, $options ) = @_;
173 # too early for this check
174 #find_type_constraint("ClassName")->check($class)
175 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
183 $options{name} ||= "__ANON__";
185 Moose::Meta::TypeConstraint::Role->new( %options );
189 sub find_or_create_type_constraint ($;$) {
190 my ( $type_constraint_name, $options_for_anon_type ) = @_;
192 if ( my $constraint = find_or_parse_type_constraint($type_constraint_name) ) {
195 elsif ( defined $options_for_anon_type ) {
197 # if there is no $options_for_anon_type
198 # specified, then we assume they don't
199 # want to create one, and return nothing.
201 # otherwise assume that we should create
202 # an ANON type with the $options_for_anon_type
203 # options which can be passed in. It should
204 # be noted that these don't get registered
205 # so we need to return it.
207 return Moose::Meta::TypeConstraint->new(
209 %{$options_for_anon_type}
216 sub find_or_create_isa_type_constraint ($) {
217 my $type_constraint_name = shift;
218 find_or_parse_type_constraint($type_constraint_name) || create_class_type_constraint($type_constraint_name)
221 sub find_or_create_does_type_constraint ($) {
222 my $type_constraint_name = shift;
223 find_or_parse_type_constraint($type_constraint_name) || create_role_type_constraint($type_constraint_name)
226 sub find_or_parse_type_constraint ($) {
227 my $type_constraint_name = normalize_type_constraint_name(shift);
230 if ($constraint = find_type_constraint($type_constraint_name)) {
232 } elsif (_detect_type_constraint_union($type_constraint_name)) {
233 $constraint = create_type_constraint_union($type_constraint_name);
234 } elsif (_detect_parameterized_type_constraint($type_constraint_name)) {
235 $constraint = create_parameterized_type_constraint($type_constraint_name);
240 $REGISTRY->add_type_constraint($constraint);
244 sub normalize_type_constraint_name {
245 my $type_constraint_name = shift @_;
246 $type_constraint_name =~ s/\s//g;
247 return $type_constraint_name;
253 local $Carp::CarpLevel = $Carp::CarpLevel + 1;
254 Carp::confess($error);
257 ## --------------------------------------------------------
258 ## exported functions ...
259 ## --------------------------------------------------------
261 sub find_type_constraint ($) {
264 if ( blessed $type and $type->isa("Moose::Meta::TypeConstraint") ) {
268 return unless $REGISTRY->has_type_constraint($type);
269 return $REGISTRY->get_type_constraint($type);
273 sub register_type_constraint ($) {
274 my $constraint = shift;
275 Moose->throw_error("can't register an unnamed type constraint") unless defined $constraint->name;
276 $REGISTRY->add_type_constraint($constraint);
283 splice(@_, 1, 0, undef);
284 goto &_create_type_constraint;
287 sub subtype ($$;$$$) {
289 # this adds an undef for the name
290 # if this is an anon-subtype:
291 # subtype(Num => where { $_ % 2 == 0 }) # anon 'even' subtype
292 # but if the last arg is not a code
293 # ref then it is a subtype alias:
294 # subtype(MyNumbers => as Num); # now MyNumbers is the same as Num
295 # ... yeah I know it's ugly code
297 unshift @_ => undef if scalar @_ <= 2 && ('CODE' eq ref($_[1]));
298 goto &_create_type_constraint;
301 sub class_type ($;$) {
302 register_type_constraint(
303 create_class_type_constraint(
305 ( defined($_[1]) ? $_[1] : () ),
310 sub role_type ($;$) {
311 register_type_constraint(
312 create_role_type_constraint(
314 ( defined($_[1]) ? $_[1] : () ),
320 my ($type_name, @coercion_map) = @_;
321 _install_type_coercions($type_name, \@coercion_map);
325 sub from ($) { $_[0] }
326 sub where (&) { $_[0] }
327 sub via (&) { $_[0] }
329 sub message (&) { +{ message => $_[0] } }
330 sub optimize_as (&) { +{ optimized => $_[0] } }
333 my ($type_name, @values) = @_;
335 # if only an array-ref is passed then
336 # you get an anon-enum
338 if (ref $type_name eq 'ARRAY' && !@values) {
339 @values = @$type_name;
342 (scalar @values >= 2)
343 || Moose->throw_error("You must have at least two values to enumerate through");
344 my %valid = map { $_ => 1 } @values;
346 register_type_constraint(
347 create_enum_type_constraint(
354 sub create_enum_type_constraint ($$) {
355 my ( $type_name, $values ) = @_;
357 Moose::Meta::TypeConstraint::Enum->new(
358 name => $type_name || '__ANON__',
363 ## --------------------------------------------------------
364 ## desugaring functions ...
365 ## --------------------------------------------------------
367 sub _create_type_constraint ($$$;$$) {
372 my ($message, $optimized);
374 $message = $_->{message} if exists $_->{message};
375 $optimized = $_->{optimized} if exists $_->{optimized};
378 my $pkg_defined_in = scalar(caller(0));
381 my $type = $REGISTRY->get_type_constraint($name);
383 ( $type->_package_defined_in eq $pkg_defined_in )
385 "The type constraint '$name' has already been created in "
386 . $type->_package_defined_in
387 . " and cannot be created again in "
392 my $class = "Moose::Meta::TypeConstraint";
394 # FIXME should probably not be a special case
395 if ( defined $parent and $parent = find_or_parse_type_constraint($parent) ) {
396 $class = "Moose::Meta::TypeConstraint::Parameterizable"
397 if $parent->isa("Moose::Meta::TypeConstraint::Parameterizable");
400 my $constraint = $class->new(
401 name => $name || '__ANON__',
402 package_defined_in => $pkg_defined_in,
404 ($parent ? (parent => $parent ) : ()),
405 ($check ? (constraint => $check) : ()),
406 ($message ? (message => $message) : ()),
407 ($optimized ? (optimized => $optimized) : ()),
411 # if we have a type constraint union, and no
412 # type check, this means we are just aliasing
413 # the union constraint, which means we need to
414 # handle this differently.
416 if (not(defined $check)
417 && $parent->isa('Moose::Meta::TypeConstraint::Union')
418 && $parent->has_coercion
420 $constraint->coercion(Moose::Meta::TypeCoercion::Union->new(
421 type_constraint => $parent
425 $REGISTRY->add_type_constraint($constraint)
431 sub _install_type_coercions ($$) {
432 my ($type_name, $coercion_map) = @_;
433 my $type = find_type_constraint($type_name);
435 || Moose->throw_error("Cannot find type '$type_name', perhaps you forgot to load it.");
436 if ($type->has_coercion) {
437 $type->coercion->add_type_coercions(@$coercion_map);
440 my $type_coercion = Moose::Meta::TypeCoercion->new(
441 type_coercion_map => $coercion_map,
442 type_constraint => $type
444 $type->coercion($type_coercion);
448 ## --------------------------------------------------------
449 ## type notation parsing ...
450 ## --------------------------------------------------------
453 # All I have to say is mugwump++ cause I know
454 # do not even have enough regexp-fu to be able
455 # to have written this (I can only barely
456 # understand it as it is)
461 my $valid_chars = qr{[\w:]};
462 my $type_atom = qr{ $valid_chars+ };
466 my $type = qr{ $valid_chars+ (?: \[ \s* (??{$any}) \s* \] )? }x;
467 my $type_capture_parts = qr{ ($valid_chars+) (?: \[ \s* ((??{$any})) \s* \] )? }x;
468 my $type_with_parameter = qr{ $valid_chars+ \[ \s* (??{$any}) \s* \] }x;
470 my $op_union = qr{ \s* \| \s* }x;
471 my $union = qr{ $type (?: $op_union $type )+ }x;
473 ## New Stuff for structured types.
475 my $indirection = qr{=>};
476 my $divider_ops = qr{ $comma | $indirection }x;
477 my $structure_divider = qr{\s* $divider_ops \s*}x;
478 my $structure_elements = qr{ ($type $structure_divider*)+ }x;
480 $any = qr{ $type | $union | $structure_elements }x;
482 sub _parse_parameterized_type_constraint {
483 { no warnings 'void'; $any; } # force capture of interpolated lexical
484 my($base, $elements) = ($_[0] =~ m{ $type_capture_parts }x);
485 return ($base,$elements);
488 sub _detect_parameterized_type_constraint {
489 { no warnings 'void'; $any; } # force capture of interpolated lexical
490 $_[0] =~ m{ ^ $type_with_parameter $ }x;
493 sub _parse_type_constraint_union {
494 { no warnings 'void'; $any; } # force capture of interpolated lexical
497 while ( $given =~ m{ \G (?: $op_union )? ($type) }gcx ) {
500 (pos($given) eq length($given))
501 || Moose->throw_error("'$given' didn't parse (parse-pos="
509 sub _detect_type_constraint_union {
510 { no warnings 'void'; $any; } # force capture of interpolated lexical
511 $_[0] =~ m{^ $type $op_union $type ( $op_union .* )? $}x;
515 ## --------------------------------------------------------
516 # define some basic built-in types
517 ## --------------------------------------------------------
519 type 'Any' => where { 1 }; # meta-type including all
520 type 'Item' => where { 1 }; # base-type
522 subtype 'Undef' => as 'Item' => where { !defined($_) };
523 subtype 'Defined' => as 'Item' => where { defined($_) };
527 => where { !defined($_) || $_ eq "" || "$_" eq '1' || "$_" eq '0' };
531 => where { !ref($_) }
532 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Value;
537 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Ref;
542 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Str;
546 => where { Scalar::Util::looks_like_number($_) }
547 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Num;
551 => where { "$_" =~ /^-?[0-9]+$/ }
552 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Int;
554 subtype 'ScalarRef' => as 'Ref' => where { ref($_) eq 'SCALAR' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ScalarRef;
555 subtype 'CodeRef' => as 'Ref' => where { ref($_) eq 'CODE' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::CodeRef;
556 subtype 'RegexpRef' => as 'Ref' => where { ref($_) eq 'Regexp' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::RegexpRef;
557 subtype 'GlobRef' => as 'Ref' => where { ref($_) eq 'GLOB' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::GlobRef;
560 # scalar filehandles are GLOB refs,
561 # but a GLOB ref is not always a filehandle
564 => where { Scalar::Util::openhandle($_) || ( blessed($_) && $_->isa("IO::Handle") ) }
565 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::FileHandle;
568 # blessed(qr/.../) returns true,.. how odd
571 => where { blessed($_) && blessed($_) ne 'Regexp' }
572 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Object;
576 => where { $_->can('does') }
577 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Role;
579 my $_class_name_checker = sub {
584 => where { Class::MOP::is_class_loaded($_) }
585 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ClassName;
587 ## --------------------------------------------------------
588 # parameterizable types ...
590 $REGISTRY->add_type_constraint(
591 Moose::Meta::TypeConstraint::Parameterizable->new(
593 package_defined_in => __PACKAGE__,
594 parent => find_type_constraint('Ref'),
595 constraint => sub { ref($_) eq 'ARRAY' },
596 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::ArrayRef,
597 constraint_generator => sub {
598 my $type_parameter = shift;
599 my $check = $type_parameter->_compiled_type_constraint;
601 foreach my $x (@$_) {
602 ($check->($x)) || return
609 $REGISTRY->add_type_constraint(
610 Moose::Meta::TypeConstraint::Parameterizable->new(
612 package_defined_in => __PACKAGE__,
613 parent => find_type_constraint('Ref'),
614 constraint => sub { ref($_) eq 'HASH' },
615 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::HashRef,
616 constraint_generator => sub {
617 my $type_parameter = shift;
618 my $check = $type_parameter->_compiled_type_constraint;
620 foreach my $x (values %$_) {
621 ($check->($x)) || return
628 $REGISTRY->add_type_constraint(
629 Moose::Meta::TypeConstraint::Parameterizable->new(
631 package_defined_in => __PACKAGE__,
632 parent => find_type_constraint('Item'),
633 constraint => sub { 1 },
634 constraint_generator => sub {
635 my $type_parameter = shift;
636 my $check = $type_parameter->_compiled_type_constraint;
638 return 1 if not(defined($_)) || $check->($_);
645 my @PARAMETERIZABLE_TYPES = map {
646 $REGISTRY->get_type_constraint($_)
647 } qw[ArrayRef HashRef Maybe];
649 sub get_all_parameterizable_types { @PARAMETERIZABLE_TYPES }
650 sub add_parameterizable_type {
652 (blessed $type && $type->isa('Moose::Meta::TypeConstraint::Parameterizable'))
653 || Moose->throw_error("Type must be a Moose::Meta::TypeConstraint::Parameterizable not $type");
654 push @PARAMETERIZABLE_TYPES => $type;
657 ## --------------------------------------------------------
658 # end of built-in types ...
659 ## --------------------------------------------------------
662 my @BUILTINS = list_all_type_constraints();
663 sub list_all_builtin_type_constraints { @BUILTINS }
674 Moose::Util::TypeConstraints - Type constraint system for Moose
678 use Moose::Util::TypeConstraints;
680 type 'Num' => where { Scalar::Util::looks_like_number($_) };
686 subtype 'NaturalLessThanTen'
689 => message { "This number ($_) is not less than ten!" };
695 enum 'RGBColors' => qw(red green blue);
699 This module provides Moose with the ability to create custom type
700 contraints to be used in attribute definition.
702 =head2 Important Caveat
704 This is B<NOT> a type system for Perl 5. These are type constraints,
705 and they are not used by Moose unless you tell it to. No type
706 inference is performed, expression are not typed, etc. etc. etc.
708 This is simply a means of creating small constraint functions which
709 can be used to simplify your own type-checking code, with the added
710 side benefit of making your intentions clearer through self-documentation.
712 =head2 Slightly Less Important Caveat
714 It is B<always> a good idea to quote your type and subtype names.
716 This is to prevent perl from trying to execute the call as an indirect
717 object call. This issue only seems to come up when you have a subtype
718 the same name as a valid class, but when the issue does arise it tends
719 to be quite annoying to debug.
721 So for instance, this:
723 subtype DateTime => as Object => where { $_->isa('DateTime') };
725 will I<Just Work>, while this:
728 subtype DateTime => as Object => where { $_->isa('DateTime') };
730 will fail silently and cause many headaches. The simple way to solve
731 this, as well as future proof your subtypes from classes which have
732 yet to have been created yet, is to simply do this:
735 subtype 'DateTime' => as 'Object' => where { $_->isa('DateTime') };
737 =head2 Default Type Constraints
739 This module also provides a simple hierarchy for Perl 5 types, here is
740 that hierarchy represented visually.
764 B<NOTE:> Any type followed by a type parameter C<[`a]> can be
765 parameterized, this means you can say:
767 ArrayRef[Int] # an array of intergers
768 HashRef[CodeRef] # a hash of str to CODE ref mappings
769 Maybe[Str] # value may be a string, may be undefined
771 B<NOTE:> Unless you parameterize a type, then it is invalid to
772 include the square brackets. I.e. C<ArrayRef[]> will be
773 literally interpreted as a type name.
775 B<NOTE:> The C<Undef> type constraint for the most part works
776 correctly now, but edge cases may still exist, please use it
779 B<NOTE:> The C<ClassName> type constraint does a complex package
780 existence check. This means that your class B<must> be loaded for
781 this type constraint to pass. I know this is not ideal for all,
782 but it is a saner restriction than most others.
784 =head2 Type Constraint Naming
786 Since the types created by this module are global, it is suggested
787 that you namespace your types just as you would namespace your
788 modules. So instead of creating a I<Color> type for your B<My::Graphics>
789 module, you would call the type I<My::Graphics::Color> instead.
791 =head2 Use with Other Constraint Modules
793 This module should play fairly nicely with other constraint
794 modules with only some slight tweaking. The C<where> clause
795 in types is expected to be a C<CODE> reference which checks
796 it's first argument and returns a boolean. Since most constraint
797 modules work in a similar way, it should be simple to adapt
798 them to work with Moose.
800 For instance, this is how you could use it with
801 L<Declare::Constraints::Simple> to declare a completely new type.
803 type 'HashOfArrayOfObjects'
806 -values => IsArrayRef( IsObject ));
808 For more examples see the F<t/200_examples/204_example_w_DCS.t>
811 Here is an example of using L<Test::Deep> and it's non-test
812 related C<eq_deeply> function.
814 type 'ArrayOfHashOfBarsAndRandomNumbers'
817 array_each(subhashof({
819 random_number => ignore()
823 For a complete example see the
824 F<t/200_examples/205_example_w_TestDeep.t> test file.
828 =head2 Type Constraint Constructors
830 The following functions are used to create type constraints.
831 They will then register the type constraints in a global store
832 where Moose can get to them if it needs to.
834 See the L<SYNOPSIS> for an example of how to use these.
838 =item B<type ($name, $where_clause)>
840 This creates a base type, which has no parent.
842 =item B<subtype ($name, $parent, $where_clause, ?$message)>
844 This creates a named subtype.
846 =item B<subtype ($parent, $where_clause, ?$message)>
848 This creates an unnamed subtype and will return the type
849 constraint meta-object, which will be an instance of
850 L<Moose::Meta::TypeConstraint>.
852 =item B<class_type ($class, ?$options)>
854 Creates a type constraint with the name C<$class> and the metaclass
855 L<Moose::Meta::TypeConstraint::Class>.
857 =item B<role_type ($role, ?$options)>
859 Creates a type constraint with the name C<$role> and the metaclass
860 L<Moose::Meta::TypeConstraint::Role>.
862 =item B<enum ($name, @values)>
864 This will create a basic subtype for a given set of strings.
865 The resulting constraint will be a subtype of C<Str> and
866 will match any of the items in C<@values>. It is case sensitive.
867 See the L<SYNOPSIS> for a simple example.
869 B<NOTE:> This is not a true proper enum type, it is simple
870 a convient constraint builder.
872 =item B<enum (\@values)>
874 If passed an ARRAY reference instead of the C<$name>, C<@values> pair,
875 this will create an unnamed enum. This can then be used in an attribute
878 has 'sort_order' => (
880 isa => enum([qw[ ascending descending ]]),
885 This is just sugar for the type constraint construction syntax.
889 This is just sugar for the type constraint construction syntax.
891 Takes a block/code ref as an argument. When the type constraint is
892 tested, the supplied code is run with the value to be tested in
893 $_. This block should return true or false to indicate whether or not
894 the constraint check passed.
898 This is just sugar for the type constraint construction syntax.
900 Takes a block/code ref as an argument. When the type constraint fails,
901 then the code block is run (with the value provided in $_). This code
902 ref should return a string, which will be used in the text of the
907 This can be used to define a "hand optimized" version of your
908 type constraint which can be used to avoid traversing a subtype
909 constraint heirarchy.
911 B<NOTE:> You should only use this if you know what you are doing,
912 all the built in types use this, so your subtypes (assuming they
913 are shallow) will not likely need to use this.
917 =head2 Type Coercion Constructors
919 Type constraints can also contain type coercions as well. If you
920 ask your accessor to coerce, then Moose will run the type-coercion
921 code first, followed by the type constraint check. This feature
922 should be used carefully as it is very powerful and could easily
923 take off a limb if you are not careful.
925 See the L<SYNOPSIS> for an example of how to use these.
933 This is just sugar for the type coercion construction syntax.
937 This is just sugar for the type coercion construction syntax.
941 =head2 Type Constraint Construction & Locating
945 =item B<normalize_type_constraint_name ($type_constraint_name)>
947 Given a string that is expected to match a type constraint, will normalize the
948 string so that extra whitespace and newlines are removed.
950 =item B<create_type_constraint_union ($pipe_seperated_types | @type_constraint_names)>
952 Given string with C<$pipe_seperated_types> or a list of C<@type_constraint_names>,
953 this will return a L<Moose::Meta::TypeConstraint::Union> instance.
955 =item B<create_parameterized_type_constraint ($type_name)>
957 Given a C<$type_name> in the form of:
959 BaseType[ContainerType]
961 this will extract the base type and container type and build an instance of
962 L<Moose::Meta::TypeConstraint::Parameterized> for it.
964 =item B<create_class_type_constraint ($class, ?$options)>
966 Given a class name it will create a new L<Moose::Meta::TypeConstraint::Class>
967 object for that class name.
969 =item B<create_role_type_constraint ($role, ?$options)>
971 Given a role name it will create a new L<Moose::Meta::TypeConstraint::Role>
972 object for that role name.
974 =item B<create_enum_type_constraint ($name, $values)>
976 =item B<find_or_parse_type_constraint ($type_name)>
978 This will attempt to find or create a type constraint given the a C<$type_name>.
979 If it cannot find it in the registry, it will see if it should be a union or
980 container type an create one if appropriate
982 =item B<find_or_create_type_constraint ($type_name, ?$options_for_anon_type)>
984 This function will first call C<find_or_parse_type_constraint> with the type name.
986 If no type is found or created, but C<$options_for_anon_type> are provided, it
987 will create the corresponding type.
989 This was used by the C<does> and C<isa> parameters to L<Moose::Meta::Attribute>
990 and are now superseded by C<find_or_create_isa_type_constraint> and
991 C<find_or_create_does_type_constraint>.
993 =item B<find_or_create_isa_type_constraint ($type_name)>
995 =item B<find_or_create_does_type_constraint ($type_name)>
997 Attempts to parse the type name using L<find_or_parse_type_constraint> and if
998 no appropriate constraint is found will create a new anonymous one.
1000 The C<isa> variant will use C<create_class_type_constraint> and the C<does>
1001 variant will use C<create_role_type_constraint>.
1003 =item B<find_type_constraint ($type_name)>
1005 This function can be used to locate a specific type constraint
1006 meta-object, of the class L<Moose::Meta::TypeConstraint> or a
1007 derivative. What you do with it from there is up to you :)
1009 =item B<register_type_constraint ($type_object)>
1011 This function will register a named type constraint with the type registry.
1013 =item B<get_type_constraint_registry>
1015 Fetch the L<Moose::Meta::TypeConstraint::Registry> object which
1016 keeps track of all type constraints.
1018 =item B<list_all_type_constraints>
1020 This will return a list of type constraint names, you can then
1021 fetch them using C<find_type_constraint ($type_name)> if you
1024 =item B<list_all_builtin_type_constraints>
1026 This will return a list of builtin type constraints, meaning,
1027 those which are defined in this module. See the section
1028 labeled L<Default Type Constraints> for a complete list.
1030 =item B<export_type_constraints_as_functions>
1032 This will export all the current type constraints as functions
1033 into the caller's namespace. Right now, this is mostly used for
1034 testing, but it might prove useful to others.
1036 =item B<get_all_parameterizable_types>
1038 This returns all the parameterizable types that have been registered.
1040 =item B<add_parameterizable_type ($type)>
1042 Adds C<$type> to the list of parameterizable types
1046 =head2 Namespace Management
1052 This will remove all the type constraint keywords from the
1053 calling class namespace.
1059 All complex software has bugs lurking in it, and this module is no
1060 exception. If you find a bug please either email me, or add the bug
1065 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1067 =head1 COPYRIGHT AND LICENSE
1069 Copyright 2006-2008 by Infinity Interactive, Inc.
1071 L<http://www.iinteractive.com>
1073 This library is free software; you can redistribute it and/or modify
1074 it under the same terms as Perl itself.