In article <[EMAIL PROTECTED]>, Robert Dailey <[EMAIL PROTECTED]> wrote:
> Hi, > > Is there a way to force a specific parameter in a function to be a > specific type? For example, say the first parameter in a function of > mine is required to be a string. If the user passes in an integer, I > want to notify them that they should pass in a string, not an integer. At present, there isn't any built-in way to do this (see the recent thread "PEP 3107 and stronger typing" for a long discussion). However, you can use assert and isinstance() to check it manually: def foo(a): assert isinstance(a, str), "argument 'a' must be a string" I wouldn't advocate getting carried away with this pattern since it precludes your function from working with duck typing and defeats some of the dynamic nature of Python. On the other hand, without such checks the resulting exceptions from assuming an argument is one type when it is another can be a bit misleading. Dave -- http://mail.python.org/mailman/listinfo/python-list
