-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 >>>>> "Matthias" == Matthias Kaeppler <[EMAIL PROTECTED]> writes: Matthias> sorry for my ignorance, but after reading the Python Matthias> tutorial on python.org, I'm sort of, well surprised about Matthias> the lack of OOP capabilities in python. Honestly, I don't Matthias> even see the point at all of how OO actually works in Matthias> Python.
It's very common for Python newbies, especially those with backgrounds in languages such as C++, Java etc. to not really 'get' the Python way of handling types until they've had a fair amount of experience with Python. If you want to program Pythonically, you must first unlearn a number of things. For instance, in e.g. the Java tradition, if a function needs a triangle object, it'll take a triangle object as an argument. If it can handle any type of shape, it'll either take a shape base class instance as an argument or there'll be some kind of shape interface that it can take. Argument types are strictly controlled. Not so with Python. A Python solution will typically take any type of object as an argument so long as it behaves as expected, and if it doesn't, we deal with the resulting exception (or don't, depending on what we're trying to accomplish). For instance, if the function from before that wants a shape really only needs to call an area method, anything with an area method can be used successfully as an argument. Some have dubbed this kind of type check 'duck typing': if it walks like a duck and quacks like a duck, chances are it'll be a duck. To those who are used to (more or less) strong, static type checks, this will seem a reckless approach, but it really works rather well, and subtle type errors are, in my experience, as rare in Python as in any other language. In my opinion, the tricks the C*/Java people occasionally do to get around the type system, such as casting to the fundamental object type, are worse because they're seldom expected and resulting errors thus typically more subtle. In my very first post on this news group a number of years ago, I asked for an equivalent of Java's interfaces. The only reply I got was that I didn't need them. While the reason was very obvious, even with what I knew about Python, it still took a while to sink in. From what I can tell, you're in somewhat the same situation, and the two of us are far from unique. As I said in the beginning, Python newbies with a background in statically typed languages typically have a lot to unlearn, but in my opinion, it's well worth it. Martin -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (GNU/Linux) Comment: Using Mailcrypt+GnuPG <http://www.gnupg.org> iEYEARECAAYFAkOba8oACgkQYu1fMmOQldXzcgCg0JEGTEG7xC/yAx8C1VFO8H1R LWwAnRJ8AxHBe8YoHcDC5oGRfYaPHTfX =HdTR -----END PGP SIGNATURE----- -- http://mail.python.org/mailman/listinfo/python-list
