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PatternProgramming (last edited 2008-11-15 13:59:47 by localhost)

-  ⇤ ← Revision 5 as of 2003-11-17 22:11:21 → 
  Size: 827
  Editor: yermat
  Comment:
+   ← Revision 6 as of 2003-11-17 22:14:15 → ⇥
  Size: 85
  Editor: yermat
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 3:
-= Singleton =
+= Pattern Programming =
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-See also http://c2.com/cgi/wiki?PythonSingleton and http://www.python.org/workshops/1997-10/proceedings/savikko.html

=== classmethod ===
----
''' pro '''

 * You can use both as simple class or as a singleton.
 * You do not need to write code for each class you want to act as singleton.

----
''' cons '''



{{{
#!python
# Code is Public Domain.
class Singleton:
    _singleton = None
    
    def getSingleton(cls):
        if not Singleton._singleton:
            Singleton._singleton = cls()
        return Singleton._singleton

    getSingleton = classmethod(getSingleton)


class Test(Singleton):
    def test(self):
        print self.__class__,id(self)


t1 = Test.getSingleton()
t2 = Test.getSingleton()

t1.test()
t2.test()
}}}
+=== GoF ===
 * Singleton