# phpman > info > Type::Library Type::[Library(3pm)](https://www.chedong.com/phpMan.php/man/Library/3pm/markdown) User Contributed Perl Documentation Type::[Library(3pm)](https://www.chedong.com/phpMan.php/man/Library/3pm/markdown) NAME [Type::Library](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ALibrary/markdown) - tiny, yet Moo(se)-compatible type libraries SYNOPSIS package [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) { use [Scalar::Util](https://www.chedong.com/phpMan.php/perldoc/Scalar%3A%3AUtil/markdown) qw(looks_like_number); use [Type::Library](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ALibrary/markdown) -base; use [Type::Tiny](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ATiny/markdown); my $NUM = "[Type::Tiny](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ATiny/markdown)"->new( name => "Number", constraint => sub { looks_like_number($_) }, message => sub { "$_ ain't a number" }, ); __PACKAGE__->meta->add_type($NUM); __PACKAGE__->meta->make_immutable; } package Ermintrude { use Moo; use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw(Number); has favourite_number => (is => "ro", isa => Number); } package Bullwinkle { use Moose; use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw(Number); has favourite_number => (is => "ro", isa => Number); } package Maisy { use Mouse; use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw(Number); has favourite_number => (is => "ro", isa => Number); } STATUS This module is covered by the Type-Tiny stability policy. DESCRIPTION [Type::Library](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ALibrary/markdown) is a tiny class for creating [MooseX::Types](https://www.chedong.com/phpMan.php/perldoc/MooseX%3A%3ATypes/markdown)-like type libraries which are compatible with Moo, Moose and Mouse. If you're reading this because you want to create a type library, then you're probably better off reading [Type::Tiny::Manual::Libraries](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ATiny%3A%3AManual%3A%3ALibraries/markdown). Methods A type library is a singleton class. Use the "meta" method to get a blessed object which other methods can get called on. For example: [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown)->meta->add_type($foo); "add_type($type)" or "add_type(%opts)" Add a type to the library. If %opts is given, then this method calls "[Type::Tiny](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ATiny/markdown)->new(%opts)" first, and adds the resultant type. Adding a type named "Foo" to the library will automatically define four functions in the library's namespace: "Foo" Returns the [Type::Tiny](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ATiny/markdown) object. "is_Foo($value)" Returns true iff $value passes the type constraint. "assert_Foo($value)" Returns $value iff $value passes the type constraint. Dies otherwise. "to_Foo($value)" Coerces the value to the type. "get_type($name)" Gets the "[Type::Tiny](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ATiny/markdown)" object corresponding to the name. "has_type($name)" Boolean; returns true if the type exists in the library. "type_names" List all types defined by the library. "add_coercion($c)" or "add_coercion(%opts)" Add a standalone coercion to the library. If %opts is given, then this method calls "[Type::Coercion](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ACoercion/markdown)->new(%opts)" first, and adds the resultant coercion. Adding a coercion named "FooFromBar" to the library will automatically define a function in the library's namespace: "FooFromBar" Returns the [Type::Coercion](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ACoercion/markdown) object. "get_coercion($name)" Gets the "[Type::Coercion](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ACoercion/markdown)" object corresponding to the name. "has_coercion($name)" Boolean; returns true if the coercion exists in the library. "coercion_names" List all standalone coercions defined by the library. "import(@args)" [Type::Library](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ALibrary/markdown)-based libraries are exporters. "make_immutable" A shortcut for calling "$type->coercion->freeze" on every type constraint in the library. Constants "NICE_PROTOTYPES" If this is true, then [Type::Library](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ALibrary/markdown) will give parameterizable type constraints slightly the nicer prototype of "(;$)" instead of the default "(;@)". This allows constructs like: ArrayRef[Int] | HashRef[Int] ... to "just work". Export Type libraries are exporters. For the purposes of the following examples, assume that the "[Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown)" library defines types "Number" and "String". # Exports nothing. # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown); # Exports a function "String" which is a constant returning # the String type constraint. # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( String ); # Exports both String and Number as above. # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( String Number ); # Same. # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( :types ); # Exports "coerce_String" and "coerce_Number", as well as any other # coercions # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( :coercions ); # Exports a sub "is_String" so that "is_String($foo)" is equivalent # to "String->check($foo)". # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( is_String ); # Exports "is_String" and "is_Number". # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( :is ); # Exports a sub "assert_String" so that "assert_String($foo)" is # equivalent to "String->assert_return($foo)". # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( assert_String ); # Exports "assert_String" and "assert_Number". # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( :assert ); # Exports a sub "to_String" so that "to_String($foo)" is equivalent # to "String->coerce($foo)". # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( to_String ); # Exports "to_String" and "to_Number". # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( :to ); # Exports "String", "is_String", "assert_String" and "coerce_String". # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( +String ); # Exports everything. # use [Types::Mine](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AMine/markdown) qw( :all ); Type libraries automatically inherit from [Exporter::Tiny](https://www.chedong.com/phpMan.php/perldoc/Exporter%3A%3ATiny/markdown); see the documentation of that module for tips and tricks importing from libraries. BUGS Please report any bugs to <>. SEE ALSO [Type::Tiny::Manual](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ATiny%3A%3AManual/markdown). [Type::Tiny](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ATiny/markdown), [Type::Utils](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3AUtils/markdown), [Types::Standard](https://www.chedong.com/phpMan.php/perldoc/Types%3A%3AStandard/markdown), [Type::Coercion](https://www.chedong.com/phpMan.php/perldoc/Type%3A%3ACoercion/markdown). [Moose::Util::TypeConstraints](https://www.chedong.com/phpMan.php/perldoc/Moose%3A%3AUtil%3A%3ATypeConstraints/markdown), [Mouse::Util::TypeConstraints](https://www.chedong.com/phpMan.php/perldoc/Mouse%3A%3AUtil%3A%3ATypeConstraints/markdown). AUTHOR Toby Inkster <>. COPYRIGHT AND LICENCE This software is copyright (c) 2013-2014, 2017-2021 by Toby Inkster. This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. DISCLAIMER OF WARRANTIES THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. perl v5.32.1 2021-08-31 Type::[Library(3pm)](https://www.chedong.com/phpMan.php/man/Library/3pm/markdown)