1Moose::Meta::TypeConstrUasienrt(C3o)ntributed Perl DocumMeonotsaet:i:oMneta::TypeConstraint(3)
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NAME

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

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

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

17       Moose::Meta::TypeConstraint->new(%options)
18           This creates a new type constraint based on the provided %options:
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20           ·       name
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22                   The constraint name. If a name is not provided, it will be
23                   set to "__ANON__".
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25           ·       parent
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27                   A "Moose::Meta::TypeConstraint" object which is the parent
28                   type for the type being created. This is optional.
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30           ·       constraint
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32                   This is the subroutine reference that implements the actual
33                   constraint check. This defaults to a subroutine which
34                   always returns true.
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36           ·       message
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38                   A subroutine reference which is used to generate an error
39                   message when the constraint fails. This is optional.
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41           ·       coercion
42
43                   A Moose::Meta::TypeCoercion object representing the
44                   coercions to the type. This is optional.
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46           ·       optimized
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48                   This is a variant of the "constraint" parameter that is
49                   somehow optimized. Typically, this means incorporating both
50                   the type's constraint and all of its parents' constraints
51                   into a single subroutine reference.
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53       $constraint->equals($type_name_or_object)
54           Returns true if the supplied name or type object is the same as the
55           current type.
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57       $constraint->is_subtype_of($type_name_or_object)
58           Returns true if the supplied name or type object is a parent of the
59           current type.
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61       $constraint->is_a_type_of($type_name_or_object)
62           Returns true if the given type is the same as the current type, or
63           is a parent of the current type. This is a shortcut for checking
64           "equals" and "is_subtype_of".
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66       $constraint->coerce($value)
67           This will attempt to coerce the value to the type. If the type does
68           have any defined coercions this will throw an error.
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70       $constraint->check($value)
71           Returns true if the given value passes the constraint for the type.
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73       $constraint->validate($value)
74           This is similar to "check". However, if the type is valid then the
75           method returns an explicit "undef". If the type is not valid, we
76           call "$self->get_message($value)" internally to generate an error
77           message.
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79       $constraint->assert_valid($value)
80           Like "check" and "validate", this method checks whether $value is
81           valid under the constraint.  If it is, it will return true.  If it
82           is not, an exception will be thrown with the results of
83           "$self->get_message($value)".
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85       $constraint->name
86           Returns the type's name, as provided to the constructor.
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88       $constraint->parent
89           Returns the type's parent, as provided to the constructor, if any.
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91       $constraint->has_parent
92           Returns true if the type has a parent type.
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94       $constraint->parents
95           A synonym for "parent". This is useful for polymorphism with types
96           that can have more than one parent.
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98       $constraint->constraint
99           Returns the type's constraint, as provided to the constructor.
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101       $constraint->get_message($value)
102           This generates a method for the given value. If the type does not
103           have an explicit message, we generate a default message.
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105       $constraint->has_message
106           Returns true if the type has a message.
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108       $constraint->message
109           Returns the type's message as a subroutine reference.
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111       $constraint->coercion
112           Returns the type's Moose::Meta::TypeCoercion object, if one exists.
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114       $constraint->has_coercion
115           Returns true if the type has a coercion.
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117       $constraint->hand_optimized_type_constraint
118           Returns the type's hand optimized constraint, as provided to the
119           constructor via the "optimized" option.
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121       $constraint->has_hand_optimized_type_constraint
122           Returns true if the type has an optimized constraint.
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124       $constraint->create_child_type(%options)
125           This returns a new type constraint of the same class using the
126           provided %options. The "parent" option will be the current type.
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128           This method exists so that subclasses of this class can override
129           this behavior and change how child types are created.
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BUGS

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

135       Stevan Little <stevan@iinteractive.com>
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138       Copyright 2006-2010 by Infinity Interactive, Inc.
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140       <http://www.iinteractive.com>
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142       This library is free software; you can redistribute it and/or modify it
143       under the same terms as Perl itself.
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147perl v5.12.2                      2010-08-28    Moose::Meta::TypeConstraint(3)
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