Wojciech Gryc a écrit : > Hi, > > I recently started using Python and am extremely happy with how > productive it's made me, even as a new user. I'm hoping to continue > using the language for my research, and have come across a bit of a > stumbling block. > > I'm a seasoned Java programmer
So you may want to read this: http://dirtsimple.org/2004/12/python-is-not-java.html http://dirtsimple.org/2004/12/java-is-not-python-either.html > and quite a big fan of interfaces... > i.e. The idea that if I make a number of distinct classes that > implement interface X, I can pass them all as parameters to functions > or whatnot that require an X object. > > Is there something similar in Python? Yes, and it's even simpler : just pass your object. If it effectively implements the desired interface, everything will work fine !-) IOW : Python is dynamically typed, there's no parameters type declaration and no parameters type checking at compile time - so you just don't need to tell the compiler that your class implements a given interface. Anyway, this would be a waste of time since you can add/delete/replace attributes and methods at runtime either on a per-class or per-instance basis. > What I'd like to do is create a feature detection system for my work > -- specifically, a general class / interface called "Feature" and then > subclasses that implement functions like isFeaturePresent() in all of > their different and unique ways. I'd love to hear how I can do this in > Python. I'm not sure about what you exactly want to do, but FWIW, checking if an object has a given attribute is quite simple: if has_attr(obj, 'attribute_name'): print "Hurray" else: print "D'oh" Note that in Python, methods are attributes too - only they are callable. > Thanks, > Wojciech > -- http://mail.python.org/mailman/listinfo/python-list
