Mouse::Meta::Attribute(3pm)
NAME
Mouse::Meta::Attribute - The Mouse attribute metaclass
VERSION
This document describes Mouse version 0.64
METHODS
- "new(%options) -> Mouse::Meta::Attribute"
- Instantiates a new Mouse::Meta::Attribute. Does nothing else.
- It adds the following options to the constructor:
- "is => 'ro', 'rw', 'bare'"
This provides a shorthand for specifying the "reader", "writer", or "accessor" names. If the attribute is read-only ('ro') then it will have a "reader" method with the same attribute as the name.If it is read-write ('rw') then it will have an "accessor" method
with the same name. If you provide an explicit "writer" for a readwrite attribute, then you will have a "reader" with the same name
as the attribute, and a "writer" with the name you provided.Use 'bare' when you are deliberately not installing any methods
(accessor, reader, etc.) associated with this attribute; otherwise, Moose will issue a deprecation warning when this attribute is added to a metaclass. - "isa => Type"
This option accepts a type. The type can be a string, which should be a type name. If the type name is unknown, it is assumed to be a class name.This option can also accept a Moose::Meta::TypeConstraint object.If you also provide a "does" option, then your "isa" option must be a class name, and that class must do the role specified with
"does". - "does => Role"
This is short-hand for saying that the attribute's type must be an object which does the named role.This option is not yet supported.
- "coerce => Bool"
This option is only valid for objects with a type constraint
("isa"). If this is true, then coercions will be applied whenever
this attribute is set.You can make both this and the "weak_ref" option true. - "trigger => CodeRef"
This option accepts a subroutine reference, which will be called
after the attribute is set. - "required => Bool"
An attribute which is required must be provided to the constructor. An attribute which is required can also have a "default" or
"builder", which will satisfy its required-ness.A required attribute must have a "default", "builder" or a
non-"undef" "init_arg" - "lazy => Bool"
A lazy attribute must have a "default" or "builder". When an
attribute is lazy, the default value will not be calculated until
the attribute is read. - "weak_ref => Bool"
If this is true, the attribute's value will be stored as a weak
reference. - "auto_deref => Bool"
If this is true, then the reader will dereference the value when it is called. The attribute must have a type constraint which defines the attribute as an array or hash reference.
- "lazy_build => Bool"
Setting this to true makes the attribute lazy and provides a number of default methods.
has 'size' => (is => 'ro',
lazy_build => 1,);is equivalent to this:
has 'size' => (is => 'ro',
lazy => 1,
builder => '_build_size',
clearer => 'clear_size',
predicate => 'has_size',); - "associate_method(MethodName)"
- Associates a method with the attribute. Typically, this is called
internally when an attribute generates its accessors. - Currently the argument MethodName is ignored in Mouse.
- "verify_against_type_constraint(Item) -> TRUE | ERROR"
- Checks that the given value passes this attribute's type constraint.
Returns "true" on success, otherwise "confess"es. - "clone_and_inherit_options(options) -> Mouse::Meta::Attribute"
- Creates a new attribute in the owner class, inheriting options from
parent classes. Accessors and helper methods are installed. Some error checking is done. - "get_read_method_ref"
"get_write_method_ref" - Returns the subroutine reference of a method suitable for reading or
writing the attribute's value in the associated class. These methods
always return a subroutine reference, regardless of whether or not the attribute is read- or write-only.
SEE ALSO
Moose::Meta::Attribute
- Class::MOP::Attribute