mix statically typed with dynamically typed

[Yingjie Lan]

We all know that Python is dynamically typed, and dynamically typed languages are generally slower than statically typed ones. I wonder if it is possible at all for Python to mix statically-typed-ness with dynamically-typed-ness to boost up its speed a little bit, especially when speed is needed. For example, you define a function like this:

def speed(float dist, float time):
    return dist/time

then the compiler would generate code to first check parameter types (or even do some casts if appropriate, say cast an int into float) in the beginning of this function. and the rest of the function would then be compiled with the assumption that 'dist' and 'time' are of the type float.

Of course, dynamically-typed-ness is still the same as before. Python is well known for providing multiple programming paradigms, I wonder if we could also sneak this in nicely.

Any thoughts?