UR::Singleton(3) Abstract class for implementing singleton objects


package MyApp::SomeClass;
use UR;
class MyApp::SomeClass {
is => 'UR::Singleton',
has => [
foo => { is => 'Number' },
$obj = MyApp::SomeClass->get();


This class provides the infrastructure for singleton classes. Singletons are classes of which there can only be one instance, and that instance's ID is the class name.

If a class inherits from UR::Singleton, it overrides the default implementation of "get()" and "is_loaded()" in UR::Object with code that fabricates an appropriate object the first time it's needed.

Singletons are most often used as one of the parent classes for data sources within a Namespace. This makes it convienent to refer to them using only their name, as in a class definition.


  $obj = Class::Name->_singleton_object;
  $obj = $obj->_singleton_object;

Returns the object instance whether it is called as a class or object method.

  $class_name = Class::Name->_singleton_class_name;
  $class_name = $obj->_singleton_class_name;

Returns the class name whether it is called as a class or object method.