On Fri, Jun 12, 2009 at 9:48 AM, spir<denis.s...@free.fr> wrote: > Right, thank you. I continued my trials and ended with seemingly working > code, close to yours. > > # case pattern is Klass: yield String instead > if isinstance(pattern,Klass): > self = String(pattern, numMin,numMax, expression,name) > #~ self.__init__(pattern, numMin,numMax, expression,name) > return self > # else a Repetition > self = Pattern.__new__(cls,pattern, numMin,numMax, > expression,name) > return self > > I have more questions:
> 2. For the special case, as you can see the __init__ line is commented out > and it works anyway. While the docs positively assert that __init__ *won't* > be called if an object of a different type is returned, it is anyway. When you call String(...) you invoke String.__new__() and String.__init__(), so String.__init__() is not called by the normal mechanism. If your special case returned for example a cached instance of String(), then String.__init__() would not be called as part of the invocation of your __new__(). Kent _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
