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 my @type_parameters_tc
140 = $base_type_tc->parse_type_parameter($type_parameter);
141 return $base_type_tc->parameterize(@type_parameters_tc);
144 return Moose::Meta::TypeConstraint::Parameterized->new(
145 name => $base_type_tc->name . '[' . $type_parameter . ']',
146 parent => $base_type_tc,
148 find_or_create_isa_type_constraint($type_parameter),
153 #should we also support optimized checks?
154 sub create_class_type_constraint ($;$) {
155 my ( $class, $options ) = @_;
157 # too early for this check
158 #find_type_constraint("ClassName")->check($class)
159 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
167 $options{name} ||= "__ANON__";
169 Moose::Meta::TypeConstraint::Class->new( %options );
172 sub create_role_type_constraint ($;$) {
173 my ( $role, $options ) = @_;
175 # too early for this check
176 #find_type_constraint("ClassName")->check($class)
177 # || Moose->throw_error("Can't create a class type constraint because '$class' is not a class name");
185 $options{name} ||= "__ANON__";
187 Moose::Meta::TypeConstraint::Role->new( %options );
191 sub find_or_create_type_constraint ($;$) {
192 my ( $type_constraint_name, $options_for_anon_type ) = @_;
194 if ( my $constraint = find_or_parse_type_constraint($type_constraint_name) ) {
197 elsif ( defined $options_for_anon_type ) {
199 # if there is no $options_for_anon_type
200 # specified, then we assume they don't
201 # want to create one, and return nothing.
203 # otherwise assume that we should create
204 # an ANON type with the $options_for_anon_type
205 # options which can be passed in. It should
206 # be noted that these don't get registered
207 # so we need to return it.
209 return Moose::Meta::TypeConstraint->new(
211 %{$options_for_anon_type}
218 sub find_or_create_isa_type_constraint ($) {
219 my $type_constraint_name = shift;
220 find_or_parse_type_constraint($type_constraint_name) || create_class_type_constraint($type_constraint_name)
223 sub find_or_create_does_type_constraint ($) {
224 my $type_constraint_name = shift;
225 find_or_parse_type_constraint($type_constraint_name) || create_role_type_constraint($type_constraint_name)
228 sub find_or_parse_type_constraint ($) {
229 my $type_constraint_name = normalize_type_constraint_name(shift);
232 if ($constraint = find_type_constraint($type_constraint_name)) {
234 } elsif (_detect_type_constraint_union($type_constraint_name)) {
235 $constraint = create_type_constraint_union($type_constraint_name);
236 } elsif (_detect_parameterized_type_constraint($type_constraint_name)) {
237 $constraint = create_parameterized_type_constraint($type_constraint_name);
242 $REGISTRY->add_type_constraint($constraint);
246 sub normalize_type_constraint_name {
247 my $type_constraint_name = shift @_;
248 $type_constraint_name =~ s/\s//g;
249 return $type_constraint_name;
252 ## --------------------------------------------------------
253 ## exported functions ...
254 ## --------------------------------------------------------
256 sub find_type_constraint ($) {
259 if ( blessed $type and $type->isa("Moose::Meta::TypeConstraint") ) {
263 return unless $REGISTRY->has_type_constraint($type);
264 return $REGISTRY->get_type_constraint($type);
268 sub register_type_constraint ($) {
269 my $constraint = shift;
270 Moose->throw_error("can't register an unnamed type constraint") unless defined $constraint->name;
271 $REGISTRY->add_type_constraint($constraint);
278 splice(@_, 1, 0, undef);
279 goto &_create_type_constraint;
282 sub subtype ($$;$$$) {
284 # this adds an undef for the name
285 # if this is an anon-subtype:
286 # subtype(Num => where { $_ % 2 == 0 }) # anon 'even' subtype
287 # but if the last arg is not a code
288 # ref then it is a subtype alias:
289 # subtype(MyNumbers => as Num); # now MyNumbers is the same as Num
290 # ... yeah I know it's ugly code
292 unshift @_ => undef if scalar @_ <= 2 && ('CODE' eq ref($_[1]));
293 goto &_create_type_constraint;
296 sub class_type ($;$) {
297 register_type_constraint(
298 create_class_type_constraint(
300 ( defined($_[1]) ? $_[1] : () ),
305 sub role_type ($;$) {
306 register_type_constraint(
307 create_role_type_constraint(
309 ( defined($_[1]) ? $_[1] : () ),
315 my ($type_name, @coercion_map) = @_;
316 _install_type_coercions($type_name, \@coercion_map);
320 sub from ($) { $_[0] }
321 sub where (&) { $_[0] }
322 sub via (&) { $_[0] }
324 sub message (&) { +{ message => $_[0] } }
325 sub optimize_as (&) { +{ optimized => $_[0] } }
328 my ($type_name, @values) = @_;
330 # if only an array-ref is passed then
331 # you get an anon-enum
333 if (ref $type_name eq 'ARRAY' && !@values) {
334 @values = @$type_name;
337 (scalar @values >= 2)
338 || Moose->throw_error("You must have at least two values to enumerate through");
339 my %valid = map { $_ => 1 } @values;
341 register_type_constraint(
342 create_enum_type_constraint(
349 sub create_enum_type_constraint ($$) {
350 my ( $type_name, $values ) = @_;
352 Moose::Meta::TypeConstraint::Enum->new(
353 name => $type_name || '__ANON__',
358 ## --------------------------------------------------------
359 ## desugaring functions ...
360 ## --------------------------------------------------------
362 sub _create_type_constraint ($$$;$$) {
367 my ($message, $optimized);
369 $message = $_->{message} if exists $_->{message};
370 $optimized = $_->{optimized} if exists $_->{optimized};
373 my $pkg_defined_in = scalar(caller(0));
376 my $type = $REGISTRY->get_type_constraint($name);
378 ($type->_package_defined_in eq $pkg_defined_in)
379 || confess ("The type constraint '$name' has already been created in "
380 . $type->_package_defined_in . " and cannot be created again in "
385 my $class = "Moose::Meta::TypeConstraint";
387 # FIXME should probably not be a special case
388 if ( defined $parent and $parent = find_or_parse_type_constraint($parent) ) {
389 $class = "Moose::Meta::TypeConstraint::Parameterizable"
390 if $parent->isa("Moose::Meta::TypeConstraint::Parameterizable");
393 my $constraint = $class->new(
394 name => $name || '__ANON__',
395 package_defined_in => $pkg_defined_in,
397 ($parent ? (parent => $parent ) : ()),
398 ($check ? (constraint => $check) : ()),
399 ($message ? (message => $message) : ()),
400 ($optimized ? (optimized => $optimized) : ()),
404 # if we have a type constraint union, and no
405 # type check, this means we are just aliasing
406 # the union constraint, which means we need to
407 # handle this differently.
409 if (not(defined $check)
410 && $parent->isa('Moose::Meta::TypeConstraint::Union')
411 && $parent->has_coercion
413 $constraint->coercion(Moose::Meta::TypeCoercion::Union->new(
414 type_constraint => $parent
418 $REGISTRY->add_type_constraint($constraint)
424 sub _install_type_coercions ($$) {
425 my ($type_name, $coercion_map) = @_;
426 my $type = find_type_constraint($type_name);
428 || Moose->throw_error("Cannot find type '$type_name', perhaps you forgot to load it.");
429 if ($type->has_coercion) {
430 $type->coercion->add_type_coercions(@$coercion_map);
433 my $type_coercion = Moose::Meta::TypeCoercion->new(
434 type_coercion_map => $coercion_map,
435 type_constraint => $type
437 $type->coercion($type_coercion);
441 ## --------------------------------------------------------
442 ## type notation parsing ...
443 ## --------------------------------------------------------
446 # All I have to say is mugwump++ cause I know
447 # do not even have enough regexp-fu to be able
448 # to have written this (I can only barely
449 # understand it as it is)
454 my $valid_chars = qr{[\w:]};
455 my $type_atom = qr{ $valid_chars+ };
459 my $type = qr{ $valid_chars+ (?: \[ \s* (??{$any}) \s* \] )? }x;
460 my $type_capture_parts = qr{ ($valid_chars+) (?: \[ \s* ((??{$any})) \s* \] )? }x;
461 my $type_with_parameter = qr{ $valid_chars+ \[ \s* (??{$any}) \s* \] }x;
463 my $op_union = qr{ \s* \| \s* }x;
464 my $union = qr{ $type (?: $op_union $type )+ }x;
466 ## New Stuff for structured types.
468 my $indirection = qr{=>};
469 my $divider_ops = qr{ $comma | $indirection }x;
470 my $structure_divider = qr{\s* $divider_ops \s*}x;
471 my $structure_elements = qr{ ($type $structure_divider*)+ }x;
473 $any = qr{ $type | $union | $structure_elements }x;
475 sub _parse_parameterized_type_constraint {
476 { no warnings 'void'; $any; } # force capture of interpolated lexical
477 my($base, $elements) = ($_[0] =~ m{ $type_capture_parts }x);
478 return ($base,$elements);
481 sub _detect_parameterized_type_constraint {
482 { no warnings 'void'; $any; } # force capture of interpolated lexical
483 $_[0] =~ m{ ^ $type_with_parameter $ }x;
486 sub _parse_type_constraint_union {
487 { no warnings 'void'; $any; } # force capture of interpolated lexical
490 while ( $given =~ m{ \G (?: $op_union )? ($type) }gcx ) {
493 (pos($given) eq length($given))
494 || Moose->throw_error("'$given' didn't parse (parse-pos="
502 sub _detect_type_constraint_union {
503 { no warnings 'void'; $any; } # force capture of interpolated lexical
504 $_[0] =~ m{^ $type $op_union $type ( $op_union .* )? $}x;
508 ## --------------------------------------------------------
509 # define some basic built-in types
510 ## --------------------------------------------------------
512 type 'Any' => where { 1 }; # meta-type including all
513 type 'Item' => where { 1 }; # base-type
515 subtype 'Undef' => as 'Item' => where { !defined($_) };
516 subtype 'Defined' => as 'Item' => where { defined($_) };
520 => where { !defined($_) || $_ eq "" || "$_" eq '1' || "$_" eq '0' };
524 => where { !ref($_) }
525 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Value;
530 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Ref;
535 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Str;
539 => where { Scalar::Util::looks_like_number($_) }
540 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Num;
544 => where { "$_" =~ /^-?[0-9]+$/ }
545 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Int;
547 subtype 'ScalarRef' => as 'Ref' => where { ref($_) eq 'SCALAR' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ScalarRef;
548 subtype 'CodeRef' => as 'Ref' => where { ref($_) eq 'CODE' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::CodeRef;
549 subtype 'RegexpRef' => as 'Ref' => where { ref($_) eq 'Regexp' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::RegexpRef;
550 subtype 'GlobRef' => as 'Ref' => where { ref($_) eq 'GLOB' } => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::GlobRef;
553 # scalar filehandles are GLOB refs,
554 # but a GLOB ref is not always a filehandle
557 => where { Scalar::Util::openhandle($_) || ( blessed($_) && $_->isa("IO::Handle") ) }
558 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::FileHandle;
561 # blessed(qr/.../) returns true,.. how odd
564 => where { blessed($_) && blessed($_) ne 'Regexp' }
565 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Object;
569 => where { $_->can('does') }
570 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::Role;
572 my $_class_name_checker = sub {
577 => where { Class::MOP::is_class_loaded($_) }
578 => optimize_as \&Moose::Util::TypeConstraints::OptimizedConstraints::ClassName;
580 ## --------------------------------------------------------
581 # parameterizable types ...
583 $REGISTRY->add_type_constraint(
584 Moose::Meta::TypeConstraint::Parameterizable->new(
586 package_defined_in => __PACKAGE__,
587 parent => find_type_constraint('Ref'),
588 constraint => sub { ref($_) eq 'ARRAY' },
589 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::ArrayRef,
590 constraint_generator => sub {
591 my $type_parameter = shift;
592 my $check = $type_parameter->_compiled_type_constraint;
594 foreach my $x (@$_) {
595 ($check->($x)) || return
602 $REGISTRY->add_type_constraint(
603 Moose::Meta::TypeConstraint::Parameterizable->new(
605 package_defined_in => __PACKAGE__,
606 parent => find_type_constraint('Ref'),
607 constraint => sub { ref($_) eq 'HASH' },
608 optimized => \&Moose::Util::TypeConstraints::OptimizedConstraints::HashRef,
609 constraint_generator => sub {
610 my $type_parameter = shift;
611 my $check = $type_parameter->_compiled_type_constraint;
613 foreach my $x (values %$_) {
614 ($check->($x)) || return
621 $REGISTRY->add_type_constraint(
622 Moose::Meta::TypeConstraint::Parameterizable->new(
624 package_defined_in => __PACKAGE__,
625 parent => find_type_constraint('Item'),
626 constraint => sub { 1 },
627 constraint_generator => sub {
628 my $type_parameter = shift;
629 my $check = $type_parameter->_compiled_type_constraint;
631 return 1 if not(defined($_)) || $check->($_);
638 my @PARAMETERIZABLE_TYPES = map {
639 $REGISTRY->get_type_constraint($_)
640 } qw[ArrayRef HashRef Maybe];
642 sub get_all_parameterizable_types { @PARAMETERIZABLE_TYPES }
643 sub add_parameterizable_type {
645 (blessed $type && $type->isa('Moose::Meta::TypeConstraint::Parameterizable'))
646 || Moose->throw_error("Type must be a Moose::Meta::TypeConstraint::Parameterizable not $type");
647 push @PARAMETERIZABLE_TYPES => $type;
650 ## --------------------------------------------------------
651 # end of built-in types ...
652 ## --------------------------------------------------------
655 my @BUILTINS = list_all_type_constraints();
656 sub list_all_builtin_type_constraints { @BUILTINS }
667 Moose::Util::TypeConstraints - Type constraint system for Moose
671 use Moose::Util::TypeConstraints;
673 type 'Num' => where { Scalar::Util::looks_like_number($_) };
679 subtype 'NaturalLessThanTen'
682 => message { "This number ($_) is not less than ten!" };
688 enum 'RGBColors' => qw(red green blue);
692 This module provides Moose with the ability to create custom type
693 contraints to be used in attribute definition.
695 =head2 Important Caveat
697 This is B<NOT> a type system for Perl 5. These are type constraints,
698 and they are not used by Moose unless you tell it to. No type
699 inference is performed, expression are not typed, etc. etc. etc.
701 This is simply a means of creating small constraint functions which
702 can be used to simplify your own type-checking code, with the added
703 side benefit of making your intentions clearer through self-documentation.
705 =head2 Slightly Less Important Caveat
707 It is B<always> a good idea to quote your type and subtype names.
709 This is to prevent perl from trying to execute the call as an indirect
710 object call. This issue only seems to come up when you have a subtype
711 the same name as a valid class, but when the issue does arise it tends
712 to be quite annoying to debug.
714 So for instance, this:
716 subtype DateTime => as Object => where { $_->isa('DateTime') };
718 will I<Just Work>, while this:
721 subtype DateTime => as Object => where { $_->isa('DateTime') };
723 will fail silently and cause many headaches. The simple way to solve
724 this, as well as future proof your subtypes from classes which have
725 yet to have been created yet, is to simply do this:
728 subtype 'DateTime' => as 'Object' => where { $_->isa('DateTime') };
730 =head2 Default Type Constraints
732 This module also provides a simple hierarchy for Perl 5 types, here is
733 that hierarchy represented visually.
757 B<NOTE:> Any type followed by a type parameter C<[`a]> can be
758 parameterized, this means you can say:
760 ArrayRef[Int] # an array of intergers
761 HashRef[CodeRef] # a hash of str to CODE ref mappings
762 Maybe[Str] # value may be a string, may be undefined
764 B<NOTE:> Unless you parameterize a type, then it is invalid to
765 include the square brackets. I.e. C<ArrayRef[]> will be
766 literally interpreted as a type name.
768 B<NOTE:> The C<Undef> type constraint for the most part works
769 correctly now, but edge cases may still exist, please use it
772 B<NOTE:> The C<ClassName> type constraint does a complex package
773 existence check. This means that your class B<must> be loaded for
774 this type constraint to pass. I know this is not ideal for all,
775 but it is a saner restriction than most others.
777 =head2 Type Constraint Naming
779 Since the types created by this module are global, it is suggested
780 that you namespace your types just as you would namespace your
781 modules. So instead of creating a I<Color> type for your B<My::Graphics>
782 module, you would call the type I<My::Graphics::Color> instead.
784 =head2 Use with Other Constraint Modules
786 This module should play fairly nicely with other constraint
787 modules with only some slight tweaking. The C<where> clause
788 in types is expected to be a C<CODE> reference which checks
789 it's first argument and returns a boolean. Since most constraint
790 modules work in a similar way, it should be simple to adapt
791 them to work with Moose.
793 For instance, this is how you could use it with
794 L<Declare::Constraints::Simple> to declare a completely new type.
796 type 'HashOfArrayOfObjects'
799 -values => IsArrayRef( IsObject ));
801 For more examples see the F<t/200_examples/204_example_w_DCS.t>
804 Here is an example of using L<Test::Deep> and it's non-test
805 related C<eq_deeply> function.
807 type 'ArrayOfHashOfBarsAndRandomNumbers'
810 array_each(subhashof({
812 random_number => ignore()
816 For a complete example see the
817 F<t/200_examples/205_example_w_TestDeep.t> test file.
821 =head2 Type Constraint Constructors
823 The following functions are used to create type constraints.
824 They will then register the type constraints in a global store
825 where Moose can get to them if it needs to.
827 See the L<SYNOPSIS> for an example of how to use these.
831 =item B<type ($name, $where_clause)>
833 This creates a base type, which has no parent.
835 =item B<subtype ($name, $parent, $where_clause, ?$message)>
837 This creates a named subtype.
839 =item B<subtype ($parent, $where_clause, ?$message)>
841 This creates an unnamed subtype and will return the type
842 constraint meta-object, which will be an instance of
843 L<Moose::Meta::TypeConstraint>.
845 =item B<class_type ($class, ?$options)>
847 Creates a type constraint with the name C<$class> and the metaclass
848 L<Moose::Meta::TypeConstraint::Class>.
850 =item B<role_type ($role, ?$options)>
852 Creates a type constraint with the name C<$role> and the metaclass
853 L<Moose::Meta::TypeConstraint::Role>.
855 =item B<enum ($name, @values)>
857 This will create a basic subtype for a given set of strings.
858 The resulting constraint will be a subtype of C<Str> and
859 will match any of the items in C<@values>. It is case sensitive.
860 See the L<SYNOPSIS> for a simple example.
862 B<NOTE:> This is not a true proper enum type, it is simple
863 a convient constraint builder.
865 =item B<enum (\@values)>
867 If passed an ARRAY reference instead of the C<$name>, C<@values> pair,
868 this will create an unnamed enum. This can then be used in an attribute
871 has 'sort_order' => (
873 isa => enum([qw[ ascending descending ]]),
878 This is just sugar for the type constraint construction syntax.
882 This is just sugar for the type constraint construction syntax.
884 Takes a block/code ref as an argument. When the type constraint is
885 tested, the supplied code is run with the value to be tested in
886 $_. This block should return true or false to indicate whether or not
887 the constraint check passed.
891 This is just sugar for the type constraint construction syntax.
893 Takes a block/code ref as an argument. When the type constraint fails,
894 then the code block is run (with the value provided in $_). This code
895 ref should return a string, which will be used in the text of the
900 This can be used to define a "hand optimized" version of your
901 type constraint which can be used to avoid traversing a subtype
902 constraint heirarchy.
904 B<NOTE:> You should only use this if you know what you are doing,
905 all the built in types use this, so your subtypes (assuming they
906 are shallow) will not likely need to use this.
910 =head2 Type Coercion Constructors
912 Type constraints can also contain type coercions as well. If you
913 ask your accessor to coerce, then Moose will run the type-coercion
914 code first, followed by the type constraint check. This feature
915 should be used carefully as it is very powerful and could easily
916 take off a limb if you are not careful.
918 See the L<SYNOPSIS> for an example of how to use these.
926 This is just sugar for the type coercion construction syntax.
930 This is just sugar for the type coercion construction syntax.
934 =head2 Type Constraint Construction & Locating
938 =item B<normalize_type_constraint_name ($type_constraint_name)>
940 Given a string that is expected to match a type constraint, will normalize the
941 string so that extra whitespace and newlines are removed.
943 =item B<create_type_constraint_union ($pipe_seperated_types | @type_constraint_names)>
945 Given string with C<$pipe_seperated_types> or a list of C<@type_constraint_names>,
946 this will return a L<Moose::Meta::TypeConstraint::Union> instance.
948 =item B<create_parameterized_type_constraint ($type_name)>
950 Given a C<$type_name> in the form of:
952 BaseType[ContainerType]
954 this will extract the base type and container type and build an instance of
955 L<Moose::Meta::TypeConstraint::Parameterized> for it.
957 =item B<create_class_type_constraint ($class, ?$options)>
959 Given a class name it will create a new L<Moose::Meta::TypeConstraint::Class>
960 object for that class name.
962 =item B<create_role_type_constraint ($role, ?$options)>
964 Given a role name it will create a new L<Moose::Meta::TypeConstraint::Role>
965 object for that role name.
967 =item B<create_enum_type_constraint ($name, $values)>
969 =item B<find_or_parse_type_constraint ($type_name)>
971 This will attempt to find or create a type constraint given the a C<$type_name>.
972 If it cannot find it in the registry, it will see if it should be a union or
973 container type an create one if appropriate
975 =item B<find_or_create_type_constraint ($type_name, ?$options_for_anon_type)>
977 This function will first call C<find_or_parse_type_constraint> with the type name.
979 If no type is found or created, but C<$options_for_anon_type> are provided, it
980 will create the corresponding type.
982 This was used by the C<does> and C<isa> parameters to L<Moose::Meta::Attribute>
983 and are now superseded by C<find_or_create_isa_type_constraint> and
984 C<find_or_create_does_type_constraint>.
986 =item B<find_or_create_isa_type_constraint ($type_name)>
988 =item B<find_or_create_does_type_constraint ($type_name)>
990 Attempts to parse the type name using L<find_or_parse_type_constraint> and if
991 no appropriate constraint is found will create a new anonymous one.
993 The C<isa> variant will use C<create_class_type_constraint> and the C<does>
994 variant will use C<create_role_type_constraint>.
996 =item B<find_type_constraint ($type_name)>
998 This function can be used to locate a specific type constraint
999 meta-object, of the class L<Moose::Meta::TypeConstraint> or a
1000 derivative. What you do with it from there is up to you :)
1002 =item B<register_type_constraint ($type_object)>
1004 This function will register a named type constraint with the type registry.
1006 =item B<get_type_constraint_registry>
1008 Fetch the L<Moose::Meta::TypeConstraint::Registry> object which
1009 keeps track of all type constraints.
1011 =item B<list_all_type_constraints>
1013 This will return a list of type constraint names, you can then
1014 fetch them using C<find_type_constraint ($type_name)> if you
1017 =item B<list_all_builtin_type_constraints>
1019 This will return a list of builtin type constraints, meaning,
1020 those which are defined in this module. See the section
1021 labeled L<Default Type Constraints> for a complete list.
1023 =item B<export_type_constraints_as_functions>
1025 This will export all the current type constraints as functions
1026 into the caller's namespace. Right now, this is mostly used for
1027 testing, but it might prove useful to others.
1029 =item B<get_all_parameterizable_types>
1031 This returns all the parameterizable types that have been registered.
1033 =item B<add_parameterizable_type ($type)>
1035 Adds C<$type> to the list of parameterizable types
1039 =head1 Error Management
1045 If the caller is a Moose metaclass, use its L<Moose::Meta::Class/throw_error>
1046 routine, otherwise use L<Carp/confess>.
1050 =head2 Namespace Management
1056 This will remove all the type constraint keywords from the
1057 calling class namespace.
1063 All complex software has bugs lurking in it, and this module is no
1064 exception. If you find a bug please either email me, or add the bug
1069 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1071 =head1 COPYRIGHT AND LICENSE
1073 Copyright 2006-2008 by Infinity Interactive, Inc.
1075 L<http://www.iinteractive.com>
1077 This library is free software; you can redistribute it and/or modify
1078 it under the same terms as Perl itself.