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moosex::singleton(3) [osx man page]

MooseX::Singleton(3)					User Contributed Perl Documentation				      MooseX::Singleton(3)

NAME

       MooseX::Singleton - turn your Moose class into a singleton

VERSION

       version 0.29

SYNOPSIS

	   package MyApp;
	   use MooseX::Singleton;

	   has env => (
	       is      => 'rw',
	       isa     => 'HashRef[Str]',
	       default => sub { \%ENV },
	   );

	   package main;

	   delete MyApp->env->{PATH};
	   my $instance = MyApp->instance;
	   my $same = MyApp->instance;

DESCRIPTION

       A singleton is a class that has only one instance in an application.  "MooseX::Singleton" lets you easily upgrade (or downgrade, as it
       were) your Moose class to a singleton.

       All you should need to do to transform your class is to change "use Moose" to "use MooseX::Singleton". This module uses metaclass roles to
       do its magic, so it should cooperate with most other "MooseX" modules.

METHODS

       A singleton class will have the following additional methods:

   Singleton->instance
       This returns the singleton instance for the given package. This method does not accept any arguments. If the instance does not yet exist,
       it is created with its defaults values. This means that if your singleton requires arguments, calling "instance" will die if the object has
       not already been initialized.

   Singleton->initialize(%args)
       This method can be called only once per class. It explicitly initializes the singleton object with the given arguments.

   Singleton->_clear_instance
       This clears the existing singleton instance for the class. Obviously, this is meant for use only inside the class itself.

   Singleton->new
       This method currently works like a hybrid of "initialize" and "instance". However, calling "new" directly will probably be deprecated in a
       future release. Instead, call "initialize" or "instance" as appropriate.

BUGS

       Please report any bugs or feature requests to "bug-moosex-singleton@rt.cpan.org", or through the web interface at <http://rt.cpan.org>. We
       will be notified, and then you'll automatically be notified of progress on your bug as we make changes.

SOME CODE STOLEN FROM

       Anders Nor Berle <debolaz@gmail.com>

AND PATCHES FROM

       Ricardo SIGNES <rjbs@cpan.org>

AUTHOR

       Shawn M Moore <sartak@gmail.com>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2011 by Shawn M Moore.

       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 v5.16.2							    2011-12-08						      MooseX::Singleton(3)

Check Out this Related Man Page

MakeMethods::Emulator::Singleton(3pm)			User Contributed Perl Documentation		     MakeMethods::Emulator::Singleton(3pm)

NAME

       Class::MakeMethods::Emulator::Singleton - Emulate Class::Singleton

SYNOPSIS

	 use Class::MakeMethods::Emulator::Singleton;

	 # returns a new instance
	 my $one = Class::MakeMethods::Emulator::Singleton->instance();

	 # returns same instance
	 my $two = Class::MakeMethods::Emulator::Singleton->instance();

COMPATIBILITY

       This module emulates the functionality of Class::Singleton, using Class::MakeMethods to generate similar methods.

       You may use it directly, as shown in the SYNOPSIS above,

       Furthermore, you may call  "use Class::MakeMethods::Emulator::Singleton '-take_namespace';" to alias the Class::Singleton namespace to this
       package, and subsequent calls to the original package will be transparently handled by this emulator. To remove the emulation aliasing,
       call "use Class::MakeMethods::Emulator::Singleton '-release_namespace'".

       Caution: This affects all subsequent uses of Class::Singleton in your program, including those in other modules, and might cause unexpected
       effects.

DESCRIPTION

       A Singleton describes an object class that can have only one instance in any system.  An example of a Singleton might be a print spooler or
       system registry.  This module implements a Singleton class from which other classes can be derived.  By itself, the Class::Singleton module
       does very little other than manage the instantiation of a single object.  In deriving a class from Class::Singleton, your module will
       inherit the Singleton instantiation method and can implement whatever specific functionality is required.

SEE ALSO

       See Class::MakeMethods for general information about this distribution.

       See Class::MakeMethods::Emulator for more about this family of subclasses.

       See Class::Singleton for documentation of the original module.

       For a description and discussion of the Singleton class, see "Design Patterns", Gamma et al, Addison-Wesley, 1995, ISBN 0-201-63361-2.

       See "new" in Class::MakeMethods::Hash and "instance" in Class::MakeMethods::ClassVar for documentation of the created methods.

perl v5.10.1							    2004-09-06				     MakeMethods::Emulator::Singleton(3pm)
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