Bruno Desthuilliers <[EMAIL PROTECTED]> writes: > > Some users in fact recommend writing an explicit type signature for > > every Haskell function, which functions sort of like a unit test. > > Stop here. explicit type signature == declarative static typing != > unit test.
The user-written signature is not a declaration that informs the compiler of the type. The compiler still figures out the type by inference, just as if the signature wasn't there. The user-written signature is more like an assertion about what type the compiler will infer. If the assertion is wrong, the compiler signals an error. In that sense it's like a unit test; it makes sure the function does what the user expects. > I have few "surprises" with typing in Python. Very few. Compared to > the flexibility and simplicity gained from a dynamism that couldn't > work with static typing - even using type inference -, I don't see it > a such a wonderful gain. At least in my day to day work. I'm going to keep an eye out for it in my day-to-day coding but I'm not so convinced that I'm gaining much from Python's dynamism. However, that may be a self-fulfilling prophecy since maybe I'm cultivating a coding style that doesn't use the dynamism, and I could be doing things differently. I do find since switching to Python 2.5 and using iterators more extensively, I use the class/object features a lot less. Data that I would have put into instance attributes on objects that get passed from one function to another, instead become local variables in functions that get run over sequences, etc. -- http://mail.python.org/mailman/listinfo/python-list
