aspect::library::singleton(3pm) [debian man page]

Aspect::Library::Singleton(3pm) 			User Contributed Perl Documentation			   Aspect::Library::Singleton(3pm)

NAME

       Aspect::Library::Singleton - A singleton aspect

SYNOPSIS

	 use Aspect;
	 use Aspect::Singleton;

	 aspect Singleton => 'Foo::new';

	 my $f1 = Foo->new;
	 my $f2 = Foo->new;

	 # Both $f1 and $f2 refer to the same object

DESCRIPTION

       A reusable aspect that forces singleton behavior on a constructor. The constructor is defined by a pointcut spec: a string. regexp, or code
       ref.

       It is slightly different from "Class::Singleton" (http://search.cpan.org/~abw/Class-Singleton/Singleton.pm
       <http://search.cpan.org/~abw/Class-Singleton/Singleton.pm>):

       o   No specific name requirement on the constructor for the external interface, or for the implementation ("Class::Singleton" requires
	   clients use "instance()", and that subclasses override "_new_instance()"). With aspects, you can change the cardinality of your objects
	   without changing the clients, or the objects themselves.

       o   No need to inherit from anything- use pointcuts to specify the constructors you want to memoize. Instead of pulling singleton behavior
	   from a base class, you are pushing it in, using the aspect.

       o   No package variable or method is added to the callers namespace

       Note that this is just a special case of memoizing.

AUTHORS

       Adam Kennedy <adamk@cpan.org>

       Marcel Gruenauer <marcel@cpan.org>

       Ran Eilam <eilara@cpan.org>

COPYRIGHT

       Copyright 2001 by Marcel Gruenauer

       Some parts copyright 2009 - 2012 Adam Kennedy.

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

perl v5.14.2							    2012-02-01					   Aspect::Library::Singleton(3pm)

Apache::Singleton(3pm)					User Contributed Perl Documentation				    Apache::Singleton(3pm)

NAME

       Apache::Singleton - Singleton class for mod_perl

VERSION

       version 0.15

SYNOPSIS

	 package Printer;
	 # default:
	 #   Request for mod_perl env
	 #   Process for non-mod_perl env
	 use base qw(Apache::Singleton);

	 package Printer::PerRequest;
	 use base qw(Apache::Singleton::Request);

	 package Printer::PerProcess;
	 use base qw(Apache::Singleton::Process);

DESCRIPTION

       Apache::Singleton works the same as Class::Singleton, but with various object lifetime (scope). See Class::Singleton first.

OBJECT LIFETIME

       By inheriting one of the following sublasses of Apache::Singleton, you can change the scope of your object.

       Request
	     use base qw(Apache::Singleton::Request);

	   One instance for one request. Apache::Singleton will remove instance on each request. Implemented using mod_perl "pnotes" API. In
	   mod_perl environment (where $ENV{MOD_PERL} is defined), this is the default scope, so inheriting from Apache::Singleton would do the
	   same effect.

	   NOTE: You need "PerlOptions +GlobalRequest" in your apache configuration in order to use the Request lifetime method.

       Process
	     use base qw(Apache::Singleton::Process);

	   One instance for one httpd process. Implemented using package global. In non-mod_perl environment, this is the default scope, and you
	   may notice this is the same beaviour with Class::Singleton ;)

	   So you can use this module safely under non-mod_perl environment.

CREDITS

       Original idea by Matt Sergeant <matt@sergeant.org> and Perrin Harkins <perrin@elem.com>.

       Initial implementation and versions 0.01 to 0.07 by Tatsuhiko Miyagawa <miyagawa@bulknews.net>.

SEE ALSO

       Apache::Singleton::Request, Apache::Singleton::Process, Class::Singleton

SOURCE

       The development version is on github at http://github.com/mschout/apache-singleton <http://github.com/mschout/apache-singleton> and may be
       cloned from git://github.com/mschout/apache-singleton.git <git://github.com/mschout/apache-singleton.git>

BUGS

       Please report any bugs or feature requests to bug-apache-singleton@rt.cpan.org or through the web interface at:
	http://rt.cpan.org/Public/Dist/Display.html?Name=Apache-Singleton

AUTHOR

       Michael Schout <mschout@cpan.org>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2009 by Michael Schout.

       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 v5.14.2							    2012-04-02						    Apache::Singleton(3pm)