On Mar 9, 9:23 am, Steven D'Aprano <[EMAIL PROTECTED] cybersource.com.au> wrote: > On Sun, 09 Mar 2008 06:58:15 -0700, Guillermo wrote: > > Okay, so I think I know where's the catch now -- you must rely on the > > fact that the protocol is implemented, there's no way to enforce it if > > you're expecting a parrot-like object. You'd try to call the speak() > > method and deal with the error if there's no such method? > > That's right. That's called "duck typing" -- if all you want is something > that quacks like a duck, then it doesn't matter if it actually is a duck > or not. > > Or if you prefer: if it quacks like a duck and swims like a duck, then > it's close enough to a duck as to make no difference.
The syntax checker over here raised a warning on this one. "So close to a duck as." (I'm using the so...as construct in my Propositional Calculus program.) > try: > something.speak > except AttributeError: > # No speak() method, so it can't be a parrot. > do_something_else() It might be a dead parrot. HAR! > else: > # It seems to follow the parrot protocol. > yummy_goodness = something.speak(5) > assert "spam" in yummy_goodness.lower() P.S. Is 'resemblant' a word? So resemblant of a duck as. -- http://mail.python.org/mailman/listinfo/python-list
