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Class-Accessor-Grouped-0.10001
River stage three • 30 direct dependents • 497 total dependents
3 ++
/ Class::Accessor::Grouped

NAME

Class::Accessor::Grouped - Lets you build groups of accessors

SYNOPSIS

DESCRIPTION

This class lets you build groups of accessors that will call different getters and setters.

METHODS

mk_group_accessors

Arguments: $group, @fieldspec

Returns: none

Creates a set of accessors in a given group.

$group is the name of the accessor group for the generated accessors; they will call get_$group($field) on get and set_$group($field, $value) on set.

If you want to mimic Class::Accessor's mk_accessors $group has to be 'simple' to tell Class::Accessor::Grouped to use its own get_simple and set_simple methods.

@fieldspec is a list of field/accessor names; if a fieldspec is a scalar this is used as both field and accessor name, if a listref it is expected to be of the form [ $accessor, $field ].

mk_group_ro_accessors

Arguments: $group, @fieldspec

Returns: none

Creates a set of read only accessors in a given group. Identical to "mk_group_accessors" but accessors will throw an error if passed a value rather than setting the value.

mk_group_wo_accessors

Arguments: $group, @fieldspec

Returns: none

Creates a set of write only accessors in a given group. Identical to "mk_group_accessors" but accessors will throw an error if not passed a value rather than getting the value.

make_group_accessor

Arguments: $group, $field, $method

Returns: \&accessor_coderef ?

Called by mk_group_accessors for each entry in @fieldspec. Either returns a coderef which will be installed at &__PACKAGE__::$method, or returns undef if it elects to install the coderef on its own.

make_group_ro_accessor

Arguments: $group, $field, $method

Returns: \&accessor_coderef ?

Called by mk_group_ro_accessors for each entry in @fieldspec. Either returns a coderef which will be installed at &__PACKAGE__::$method, or returns undef if it elects to install the coderef on its own.

make_group_wo_accessor

Arguments: $group, $field, $method

Returns: \&accessor_coderef ?

Called by mk_group_wo_accessors for each entry in @fieldspec. Either returns a coderef which will be installed at &__PACKAGE__::$method, or returns undef if it elects to install the coderef on its own.

get_simple

Arguments: $field

Returns: $value

Simple getter for hash-based objects which returns the value for the field name passed as an argument.

set_simple

Arguments: $field, $new_value

Returns: $new_value

Simple setter for hash-based objects which sets and then returns the value for the field name passed as an argument.

get_inherited

Arguments: $field

Returns: $value

Simple getter for Classes and hash-based objects which returns the value for the field name passed as an argument. This behaves much like Class::Data::Accessor where the field can be set in a base class, inherited and changed in subclasses, and inherited and changed for object instances.

set_inherited

Arguments: $field, $new_value

Returns: $new_value

Simple setter for Classes and hash-based objects which sets and then returns the value for the field name passed as an argument. When called on a hash-based object it will set the appropriate hash key value. When called on a class, it will set a class level variable.

Note:: This method will die if you try to set an object variable on a non hash-based object.

get_component_class

Arguments: $field

Returns: $value

Gets the value of the specified component class.

    __PACKAGE__->mk_group_accessors('component_class' => 'result_class');

    $self->result_class->method();

    ## same as
    $self->get_component_class('result_class')->method();

set_component_class

Arguments: $field, $class

Returns: $new_value

Inherited accessor that automatically loads the specified class before setting it. This method will die if the specified class could not be loaded.

    __PACKAGE__->mk_group_accessors('component_class' => 'result_class');
    __PACKAGE__->result_class('MyClass');

    $self->result_class->method();

get_super_paths

Returns a list of 'parent' or 'super' class names that the current class inherited from.

PERFORMANCE

To provide total flexibility Class::Accessor::Grouped calls methods internally while performing get/set actions, which makes it noticeably slower than similar modules. To compensate, this module will automatically use the insanely fast Class::XSAccessor to generate the simple-group accessors, if Class::XSAccessor >= 1.06 is available on your system.

Benchmark

This is the result of a set/get/set loop benchmark on perl 5.12.1 with thread support, showcasing most popular accessor builders: Moose, Mouse, Moo, CAF, CAF_XS, XSA, and CAF_XSA:

           Rate  CAG moOse  CAF moUse  moo HANDMADE CAF_XS moUse_XS moo_XS CAF_XSA  XSA CAG_XS
 CAG      169/s   --  -21% -24%  -32% -32%     -34%   -59%     -63%   -67%    -67% -67%   -67%
 moOse    215/s  27%    --  -3%  -13% -13%     -15%   -48%     -53%   -58%    -58% -58%   -58%
 CAF      222/s  31%    3%   --  -10% -10%     -13%   -46%     -52%   -57%    -57% -57%   -57%
 moUse    248/s  46%   15%  11%    --  -0%      -3%   -40%     -46%   -52%    -52% -52%   -52%
 moo      248/s  46%   15%  11%    0%   --      -3%   -40%     -46%   -52%    -52% -52%   -52%
 HANDMADE 255/s  50%   18%  14%    3%   3%       --   -38%     -45%   -50%    -51% -51%   -51%
 CAF_XS   411/s 143%   91%  85%   66%  66%      61%     --     -11%   -20%    -20% -21%   -21%
 moUse_XS 461/s 172%  114% 107%   86%  86%      81%    12%       --   -10%    -11% -11%   -11%
 moo_XS   514/s 204%  139% 131%  107% 107%     102%    25%      12%     --     -0%  -1%    -1%
 CAF_XSA  516/s 205%  140% 132%  108% 108%     103%    26%      12%     0%      --  -0%    -0%
 XSA      519/s 206%  141% 133%  109% 109%     104%    26%      13%     1%      0%   --    -0%
 CAG_XS   519/s 206%  141% 133%  109% 109%     104%    26%      13%     1%      0%   0%     --

Benchmark program is available in the root of the repository:

Notes on Class::XSAccessor

You can force (or disable) the use of Class::XSAccessor before creating a particular simple accessor by either manipulating the global variable $Class::Accessor::Grouped::USE_XS to true or false (preferably with localization, or you can do so before runtime via the CAG_USE_XS environment variable.

Since Class::XSAccessor has no knowledge of "get_simple" and "set_simple" this module does its best to detect if you are overriding one of these methods and will fall back to using the perl version of the accessor in order to maintain consistency. However be aware that if you enable use of Class::XSAccessor (automatically or explicitly), create an object, invoke a simple accessor on that object, and then manipulate the symbol table to install a get/set_simple override - you get to keep all the pieces.

While Class::XSAccessor works surprisingly well for the amount of black magic it tries to pull off, it's still black magic. At present (Sep 2010) the module is known to have problems on Windows under heavy thread-stress (e.g. Win32+Apache+mod_perl). Thus for the time being Class::XSAccessor will not be used automatically if you are running under MSWin32.

AUTHORS

Matt S. Trout <mst@shadowcatsystems.co.uk>

Christopher H. Laco <claco@chrislaco.com>

CONTRIBUTORS

Caelum: Rafael Kitover <rkitover@cpan.org>

groditi: Guillermo Roditi <groditi@cpan.org>

Jason Plum <jason.plum@bmmsi.com>

ribasushi: Peter Rabbitson <ribasushi@cpan.org>

COPYRIGHT & LICENSE

Copyright (c) 2006-2010 Matt S. Trout <mst@shadowcatsystems.co.uk>

This program is free software; you can redistribute it and/or modify it under the same terms as perl itself.