Emulate class::singleton
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();
This module emulates the functionality of Class::Singleton, using Class::MakeMethods to generate similar methods.
You may use it directly, as shown in the \s-1SYNOPSIS\s0 above,
Furthermore, you may call \*(C`use Class::MakeMethods::Emulator::Singleton '-take_namespace';\*(C' 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 \*(C`use Class::MakeMethods::Emulator::Singleton '-release_namespace'\*(C'.
Caution: This affects all subsequent uses of Class::Singleton in your program, including those in other modules, and might cause unexpected effects.
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 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 \*(L"Design Patterns\*(R", Gamma et al, Addison-Wesley, 1995, \s-1ISBN\s0 0-201-63361-2.
See \*(L"new\*(R" in Class::MakeMethods::Hash and \*(L"instance\*(R" in Class::MakeMethods::ClassVar for documentation of the created methods.