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Class::MOP::Instance(3User Contributed Perl DocumentaClass::MOP::Instance(3pm)

NAME
       Class::MOP::Instance - Instance Meta Object

VERSION
       version 2.2200

DESCRIPTION
       The Instance Protocol controls the creation of object instances, and
       the storage of attribute values in those instances.

       Using this API directly in your own code violates encapsulation, and we
       recommend that you use the appropriate APIs in Class::MOP::Class and
       Class::MOP::Attribute instead. Those APIs in turn call the methods in
       this class as appropriate.

       This class also participates in generating inlined code by providing
       snippets of code to access an object instance.

METHODS
   Object construction
       Class::MOP::Instance->new(%options)
           This method creates a new meta-instance object.

           It accepts the following keys in %options:

           o       associated_metaclass

                   The Class::MOP::Class object for which instances will be
                   created.

           o       attributes

                   An array reference of Class::MOP::Attribute objects. These
                   are the attributes which can be stored in each instance.

   Creating and altering instances
       $metainstance->create_instance
           This method returns a reference blessed into the associated
           metaclass's class.

           The default is to use a hash reference. Subclasses can override
           this.

       $metainstance->clone_instance($instance)
           Given an instance, this method creates a new object by making
           shallow clone of the original.

   Introspection
       $metainstance->associated_metaclass
           This returns the Class::MOP::Class object associated with the meta-
           instance object.

       $metainstance->get_all_slots
           This returns a list of slot names stored in object instances. In
           almost all cases, slot names correspond directly attribute names.

       $metainstance->is_valid_slot($slot_name)
           This will return true if $slot_name is a valid slot name.

       $metainstance->get_all_attributes
           This returns a list of attributes corresponding to the attributes
           passed to the constructor.

   Operations on Instance Structures
       It's important to understand that the meta-instance object is a
       different entity from the actual instances it creates. For this reason,
       any operations on the $instance_structure always require that the
       object instance be passed to the method.

       $metainstance->get_slot_value($instance_structure, $slot_name)
       $metainstance->set_slot_value($instance_structure, $slot_name, $value)
       $metainstance->initialize_slot($instance_structure, $slot_name)
       $metainstance->deinitialize_slot($instance_structure, $slot_name)
       $metainstance->initialize_all_slots($instance_structure)
       $metainstance->deinitialize_all_slots($instance_structure)
       $metainstance->is_slot_initialized($instance_structure, $slot_name)
       $metainstance->weaken_slot_value($instance_structure, $slot_name)
       $metainstance->slot_value_is_weak($instance_structure, $slot_name)
       $metainstance->strengthen_slot_value($instance_structure, $slot_name)
       $metainstance->rebless_instance_structure($instance_structure,
       $new_metaclass)
           The exact details of what each method does should be fairly obvious
           from the method name.

   Inlinable Instance Operations
       $metainstance->is_inlinable
           This is a boolean that indicates whether or not slot access
           operations can be inlined. By default it is true, but subclasses
           can override this.

       $metainstance->inline_create_instance($class_variable)
           This method expects a string that, when inlined, will become a
           class name. This would literally be something like '$class', not an
           actual class name.

           It returns a snippet of code that creates a new object for the
           class. This is something like " bless {}, $class_name ".

       $metainstance->inline_get_is_lvalue
           Returns whether or not "inline_get_slot_value" is a valid lvalue.
           This can be used to do extra optimizations when generating inlined
           methods.

       $metainstance->inline_slot_access($instance_variable, $slot_name)
       $metainstance->inline_get_slot_value($instance_variable, $slot_name)
       $metainstance->inline_set_slot_value($instance_variable, $slot_name,
       $value)
       $metainstance->inline_initialize_slot($instance_variable, $slot_name)
       $metainstance->inline_deinitialize_slot($instance_variable, $slot_name)
       $metainstance->inline_is_slot_initialized($instance_variable,
       $slot_name)
       $metainstance->inline_weaken_slot_value($instance_variable, $slot_name)
       $metainstance->inline_strengthen_slot_value($instance_variable,
       $slot_name)
           These methods all expect two arguments. The first is the name of a
           variable, than when inlined, will represent the object instance.
           Typically this will be a literal string like '$_[0]'.

           The second argument is a slot name.

           The method returns a snippet of code that, when inlined, performs
           some operation on the instance.

       $metainstance->inline_rebless_instance_structure($instance_variable,
       $class_variable)
           This takes the name of a variable that will, when inlined,
           represent the object instance, and the name of a variable that will
           represent the class to rebless into, and returns code to rebless an
           instance into a class.

   Introspection
       Class::MOP::Instance->meta
           This will return a Class::MOP::Class instance for this class.

           It should also be noted that Class::MOP will actually bootstrap
           this module by installing a number of attribute meta-objects into
           its metaclass.

AUTHORS
       o   Stevan Little <stevan AT cpan.org>

       o   Dave Rolsky <autarch AT urth.org>

       o   Jesse Luehrs <doy AT cpan.org>

       o   Shawn M Moore <sartak AT cpan.org>

       o    ' (Yuval Kogman) <nothingmuch AT woobling.org>

       o   Karen Etheridge <ether AT cpan.org>

       o   Florian Ragwitz <rafl AT debian.org>

       o   Hans Dieter Pearcey <hdp AT cpan.org>

       o   Chris Prather <chris AT prather.org>

       o   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.

perl v5.34.0                      2022-02-06         Class::MOP::Instance(3pm)