Missing exceptions in PEP 3107

[Christoph Zwerschke]

I'm just reading PEP 3107 (function annotations) and wonder why 
exceptions are not mentioned there. I think it would be helpful if one 
could specify which exceptions can be raised by a function, similarly to 
how it is possible in C++ using the "throw" clause. The syntax would be 
something like this:

def foo(a: expr, b: expr = 5) raises expr -> expr:

The expr in that "raises" clause should be a list of Exceptions.

Having the list of possible exceptions as annotation alone would be 
already helpful. Of course it could be also discussed whether Python 
should check that the function really raises only these exceptions (as 
in C++), or we could even have checked exceptions (as in Java, but this 
seems to be a controversial issue).

Has this already been discussed, or is it in a different PEP?

-- Christoph