moose::cookbook::snack::types(3) [osx man page]
Moose::Cookbook::Snack::Types(3) User Contributed Perl Documentation Moose::Cookbook::Snack::Types(3) NAME
Moose::Cookbook::Snack::Types - Snippets of code for using Types and Type Constraints VERSION
version 2.0604 SYNOPSIS
package Point; use Moose; has 'x' => ( isa => 'Int', is => 'ro' ); has 'y' => ( isa => 'Int', is => 'rw' ); package main; use Try::Tiny; my $point = try { Point->new( x => 'fifty', y => 'forty' ); } catch { print "Oops: $_"; }; my $point; my $xval = 'forty-two'; my $xattribute = Point->meta->find_attribute_by_name('x'); my $xtype_constraint = $xattribute->type_constraint; if ( $xtype_constraint->check($xval) ) { $point = Point->new( x => $xval, y => 0 ); } else { print "Value: $xval is not an " . $xtype_constraint->name . " "; } DESCRIPTION
This is the Point example from Moose::Cookbook::Basics::Point_AttributesAndSubclassing with type checking added. If we try to assign a string value to an attribute that is an "Int", Moose will die with an explicit error message. The error will include the attribute name, as well as the type constraint name and the value which failed the constraint check. We use Try::Tiny to catch this error message. Later, we get the Moose::Meta::TypeConstraint object from a Moose::Meta::Attribute and use the Moose::Meta::TypeConstraint to check a value directly. SEE ALSO
Moose::Cookbook::Basics::Point_AttributesAndSubclassing Moose::Utils::TypeConstraints Moose::Meta::Attribute AUTHOR
Moose is maintained by the Moose Cabal, along with the help of many contributors. See "CABAL" in Moose and "CONTRIBUTORS" in Moose for details. COPYRIGHT AND LICENSE
This software is copyright (c) 2012 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. perl v5.16.2 2012-09-19 Moose::Cookbook::Snack::Types(3)
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Moose::Meta::TypeConstraint::Role(3) User Contributed Perl Documentation Moose::Meta::TypeConstraint::Role(3) NAME
Moose::Meta::TypeConstraint::Role - Role/TypeConstraint parallel hierarchy VERSION
version 2.0604 DESCRIPTION
This class represents type constraints for a role. INHERITANCE
"Moose::Meta::TypeConstraint::Role" is a subclass of Moose::Meta::TypeConstraint. METHODS
Moose::Meta::TypeConstraint::Role->new(%options) This creates a new role type constraint based on the given %options. It takes the same options as its parent, with two exceptions. First, it requires an additional option, "role", which is name of the constraint's role. Second, it automatically sets the parent to the "Object" type. The constructor also overrides the hand optimized type constraint with one it creates internally. $constraint->role Returns the role name associated with the constraint. $constraint->parents Returns all the type's parent types, corresponding to the roles that its role does. $constraint->is_subtype_of($type_name_or_object) If the given type is also a role type, then this checks that the type's role does the other type's role. Otherwise it falls back to the implementation in Moose::Meta::TypeConstraint. $constraint->create_child_type(%options) This returns a new Moose::Meta::TypeConstraint object with the type as its parent. Note that it does not return a "Moose::Meta::TypeConstraint::Role" object! BUGS
See "BUGS" in Moose for details on reporting bugs. AUTHOR
Moose is maintained by the Moose Cabal, along with the help of many contributors. See "CABAL" in Moose and "CONTRIBUTORS" in Moose for details. COPYRIGHT AND LICENSE
This software is copyright (c) 2012 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. perl v5.16.2 2012-09-19 Moose::Meta::TypeConstraint::Role(3)