NAME¶
MooseX::Clone - Fine grained cloning support for Moose objects.
SYNOPSIS¶
package Bar;
use Moose;
with qw(MooseX::Clone);
has foo => (
isa => "Foo",
traits => [qw(Clone)], # this attribute will be recursively cloned
);
package Foo;
use Moose;
# this API is used/provided by MooseX::Clone
sub clone {
my ( $self, %params ) = @_;
# ...
}
# used like this:
my $bar = Bar->new( foo => Foo->new );
my $copy = $bar->clone( foo => [ qw(Args for Foo::clone) ] );
DESCRIPTION¶
Out of the box Moose only provides very barebones cloning support in order to
maximize flexibility.
This role provides a "clone" method that makes use of the low level
cloning support already in Moose and adds selective deep cloning based on
introspection on top of that. Attributes with the "Clone" trait will
handle cloning of data within the object, typically delegating to the
attribute value's own "clone" method.
TRAITS¶
- Clone
- By default Moose objects are cloned like this:
bless { %$old }, ref $old;
By specifying the Clone trait for certain attributes custom behavior the
value's own "clone" method will be invoked.
By extending this trait you can create custom cloning for certain
attributes.
By creating "clone" methods for your objects (e.g. by composing
MooseX::Compile) you can make them interact with this trait.
- NoClone
- Specifies attributes that should be skipped entirely while
cloning.
METHODS¶
- clone %params
- Returns a clone of the object.
All attributes which do the MooseX::Clone::Meta::Attribute::Trait::Clone
role will handle cloning of that attribute. All other fields are plainly
copied over, just like in "clone_object" in Class::MOP::Class.
Attributes whose "init_arg" is in %params and who do the
"Clone" trait will get that argument passed to the
"clone" method (dereferenced). If the attribute does not
self-clone then the param is used normally by "clone_object" in
Class::MOP::Class, that is it will simply shadow the previous value, and
does not have to be an array or hash reference.
TODO¶
Refactor to work in term of a metaclass trait so that
"meta->clone_object" will still do the right thing.
THANKS¶
clkao made the food required to write this module
VERSION CONTROL¶
<
http://code2.0beta.co.uk/moose/svn/>. Ask on #moose for commit bits.
AUTHOR¶
Yuval Kogman <nothingmuch@woobling.org>
COPYRIGHT¶
Copyright (c) 2008 Yuval Kogman. All rights reserved
This program is free software; you can redistribute
it and/or modify it under the same terms as Perl itself.