Hi everybody, I need to downcast an object, and I've read repeatedly that if you need to downcast, you did something wrong in the design phase. So, instead of asking how do you downcast in python, let me explain my situation.
I have a 2-pass parser. 1st pass ends up with a bunch of superclass object, and 2nd pass is supposed to downcast those to one of subclasses so I can work with them. Details: I have a file full of lines which I parse into Line objects. I also have two subclasses of Line, namely Individual and Family. Constructor of both subclasses needs all Line objects in the file to be constructed, so I cannot construct subclass objects in the first pass. The Python way of doing this (as I understand it) would be to wrap a subclass around Line and have the Line object as an attribute of a subclass. Now, this obviously breaks polymorphism and I now have to reimplement all of Line's classes in subclasses. Although reimplementation is simple (def method(self): return self.line.method()), that way of doing things is just not elegant. So, is there any more elegant solution to my problem? Thanks in advance. -- "Now the storm has passed over me I'm left to drift on a dead calm sea And watch her forever through the cracks in the beams Nailed across the doorways of the bedrooms of my dreams" -- http://mail.python.org/mailman/listinfo/python-list
