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📛 NAME

Moose::Meta::TypeConstraint - The Moose Type Constraint metaclass

🚀 Quick Reference

Use Case	Command	Description
📦 Create a new type constraint	Moose::Meta::TypeConstraint->new(%options)	Create a type constraint with name, parent, constraint sub, message, coercion, inlining
🔍 Check if value is valid	$constraint->check($value)	Returns true if value passes constraint
🔄 Coerce a value	$constraint->coerce($value)	Attempt to coerce value to type; returns original if no coercion applies
✅ Validate and return message	$constraint->validate($value)	Returns explicit undef if valid, or error message generated by get_message
🚨 Assert valid or throw	$constraint->assert_valid($value)	Returns true if valid, throws exception with message otherwise
🧬 Check subtype relationship	$constraint->is_subtype_of($type)	Returns true if given type is a parent of current type
🔗 Get parent type	$constraint->parent	Returns parent type constraint object, if any
📝 Get constraint subroutine	$constraint->constraint	Returns the subroutine that implements the constraint check
🏗️ Create child type	$constraint->create_child_type(%options)	Returns new type constraint of same class, with this as parent

🏷️ VERSION

version 2.2200

📖 DESCRIPTION

This class represents a single type constraint. Moose's built-in type constraints, as well as constraints you define, are all stored in a Moose::Meta::TypeConstraint::Registry object as objects of this class.

🧬 INHERITANCE

"Moose::Meta::TypeConstraint" is a subclass of Class::MOP::Object.

⚙️ METHODS

• Moose::Meta::TypeConstraint->new(%options) — Creates a new type constraint. Options:
  • 📛 name — The constraint name. Defaults to "__ANON__".
  • 👨‍👩‍👦 parent — A Moose::Meta::TypeConstraint object (optional).
  • 🔍 constraint — Subroutine reference implementing the constraint check. Defaults to always true.
  • 💬 message — Subroutine reference for error message generation (optional).
  • 🔄 coercion — A Moose::Meta::TypeCoercion object (optional).
  • ⚡ inlined — Subroutine returning a string for inlining. Called as method with variable name to test (optional).
  • 🌐 inline_environment — Hash reference of variables to close over (keys are variable names, values are references).
• $constraint->equals($type_name_or_object) — Returns true if the supplied name or type object is the same as the current type.
• $constraint->is_subtype_of($type_name_or_object) — Returns true if the supplied name or type object is a parent of the current type.
• $constraint->is_a_type_of($type_name_or_object) — Returns true if the given type is the same as the current type, or is a parent. Shortcut for "equals" and "is_subtype_of".
• $constraint->coerce($value) — Attempts to coerce the value to the type. If no coercion defined, throws error. If no coercion can produce a matching value, returns the original value.
• $constraint->assert_coerce($value) — Behaves like "coerce", but if result is not valid, throws an error.
• $constraint->check($value) — Returns true if the value passes the constraint.
• $constraint->validate($value) — Similar to "check". If valid, returns explicit undef. If invalid, calls $self->get_message($value) to generate error message.
• $constraint->assert_valid($value) — Like "check" and "validate": if valid, returns true; if invalid, throws exception with message from get_message.
• $constraint->name — Returns the type's name as provided to constructor.
• $constraint->parent — Returns the type's parent, if any.
• $constraint->has_parent — Returns true if the type has a parent type.
• $constraint->parents — Returns all parent types as a list of type constraint objects.
• $constraint->constraint — Returns the constraint subroutine reference.
• $constraint->get_message($value) — Generates an error message. Falls back to default message if no explicit message defined.
• $constraint->has_message — Returns true if the type has a message subroutine.
• $constraint->message — Returns the message subroutine reference.
• $constraint->coercion — Returns the Moose::Meta::TypeCoercion object, if one exists.
• $constraint->has_coercion — Returns true if the type has a coercion.
• $constraint->can_be_inlined — Returns true if this type constraint can be inlined. A subtype of an inlinable constraint with no additional constraint inherits its parent's inlining.
• $constraint->create_child_type(%options) — Returns a new type constraint of the same class using the provided options. The "parent" option will be the current type. Exists so subclasses can override child type creation.

🐛 BUGS

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

👥 AUTHORS

• Stevan Little <stevan AT cpan.org>
• Dave Rolsky <autarch AT urth.org>
• Jesse Luehrs <doy AT cpan.org>
• Shawn M Moore <sartak AT cpan.org>
• יובל קוג'מן (Yuval Kogman) <nothingmuch AT woobling.org>
• Karen Etheridge <ether AT cpan.org>
• Florian Ragwitz <rafl AT debian.org>
• Hans Dieter Pearcey <hdp AT cpan.org>
• Chris Prather <chris AT prather.org>
• Matt S Trout <mstrout AT cpan.org>

⚖️ COPYRIGHT AND LICENSE

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.

📛 NAME 🚀 Quick Reference 🏷️ VERSION 📖 DESCRIPTION 🧬 INHERITANCE ⚙️ METHODS 🐛 BUGS 👥 AUTHORS ⚖️ COPYRIGHT AND LICENSE