Python-сообщество

import time, sys

class ConsoleController( object ):
    _iInstance = None
    
    class __Singleton:
        _selfUsed = 0
        _startTime = 0
        _endTime = 0
        _echoLevel=0
        _indentStr = '\t'
        
        def __init__(self):
            self._startTime = self.getTime()
 
        def __del__(self):
            self._endTime = self.getTime()
            timeElapsed = self._endTime - self._startTime 
            self \
                .dropText('Script finished.') \
                .dropText('Elapsed time: '+str(timeElapsed) + ' sec')
        
        def getTime(self):
            return time.time()
        
        def cEcho(self,str):
            sys.stdout.write(str)
            return self
            
        def dropLF(self):
            self.cEcho('\n')
            return self
        
        def dropText(self,str,colorize=None):
            self \
                .dropIndent() \
                .cEcho(str) \
                .dropLF()
            return self
        
        def dropIndent(self):
            self.cEcho(self._indentStr*self._echoLevel)
            return self
        
        def indentIncrease(self):
            self._echoLevel += 1
            return self
            
        def indentDecrease(self):
            self._echoLevel -= 1
            if self._echoLevel < 0:
                self._echoLevel = 0
            return self
        
    def __init__( self ):
        if ConsoleController._iInstance is None:
            ConsoleController._iInstance = ConsoleController.__Singleton()
        self.__dict__['_EventHandler_instance'] = ConsoleController._iInstance
        ConsoleController._iInstance._selfUsed += 1;

    def __getattr__(self, aAttr):
        return getattr(self._iInstance, aAttr)

    def __setattr__(self, aAttr, aValue):
        return setattr(self._iInstance, aAttr, aValue)

    def __del__(self):
        ConsoleController._iInstance._selfUsed -= 1
#        print 'Links: ' + str(ConsoleController._iInstance._selfUsed)
        if ConsoleController._iInstance._selfUsed == 0:
            self._iInstance.__del__()

import concon

def diveIn(maxDeep=1,curDeep=0):
    CC = ConsoleController()
    CC.indentIncrease()
    CC.dropText('In!')
    if maxDeep>curDeep:
        nextDeep = curDeep+1
        diveIn(maxDeep,nextDeep)
    CC.dropText('Out!')
    CC.indentDecrease()

diveIn(4)

CC = ConsoleController()
CC.dropText('Destruct message will be shown after this line!')

class Singleton(object):
    instance_ref = None

    def __new__(cls, *args, **kwargs):
        if cls.instance_ref is None or cls.instance_ref() is None:
            import weakref
            instance = object.__new__(cls, *args, **kwargs)
            cls.instance_ref = weakref.ref(instance)
            if hasattr(cls, '__hidden_init__'):
                cls.__init__ = cls.__hidden_init__
                del cls.__hidden_init__
        elif hasattr(cls, '__init__') and not hasattr(cls, '__hidden_init__'):
            cls.__hidden_init__ = cls.__init__
            cls.__init__ = lambda *args, **kwargs: None
        return cls.instance_ref()

>>> a = Singleton()
>>> b = Singleton()
>>> a is b
True