Moose::Meta::TypeConstraint::Union - A union of Moose type constraints


version 2.2206


This metaclass represents a union of type constraints. A union takes multiple type constraints, and is true if any one of its member constraints is true.


Moose::Meta::TypeConstraint::Union is a subclass of Moose::Meta::TypeConstraint.



This creates a new class type constraint based on the given %options.

It takes the same options as its parent. It also requires an additional option, type_constraints. This is an array reference containing the Moose::Meta::TypeConstraint objects that are the members of the union type. The name option defaults to the names all of these member types sorted and then joined by a pipe (|).

The constructor sets the implementation of the constraint so that is simply calls check on the newly created object.

Finally, the constructor also makes sure that the object's coercion attribute is a Moose::Meta::TypeCoercion::Union object.


This returns the array reference of type_constraints provided to the constructor.


This returns the nearest common ancestor of all the components of the union.



These two methods simply call the relevant method on each of the member type constraints in the union. If any type accepts the value, the value is valid.

With validate the error message returned includes all of the error messages returned by the member type constraints.


A type is considered equal if it is also a union type, and the two unions have the same member types.


This returns the first member type constraint for which check($value) is true, allowing you to determine which of the Union's member type constraints a given value matches.


This returns true if all of the member type constraints return true for the is_a_type_of method.


This returns true if all of the member type constraints return true for the is_subtype_of method.


This returns a new Moose::Meta::TypeConstraint object with the type as its parent.


See "BUGS" in Moose for details on reporting bugs.


  • Stevan Little <>

  • Dave Rolsky <>

  • Jesse Luehrs <>

  • Shawn M Moore <>

  • יובל קוג'מן (Yuval Kogman) <>

  • Karen Etheridge <>

  • Florian Ragwitz <>

  • Hans Dieter Pearcey <>

  • Chris Prather <>

  • Matt S Trout <>


This software is copyright (c) 2006 by Infinity Interactive, Inc.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.