[pypy-dev] Support for pure functional types.

[Maciek Fijalkowski]

  I've been wondering for some time why there is no support for pure 
functional types. Like function int -> int. In most type inference 
techniques, there is. I know, side effects. But usually we can tell that 
function has no side effects at all, so it would be nice to reduce it to 
lambda type, not just remember to enter it's block. It would make some 
things much easier.
  Anyway: when calling some lambda or local function not all bindings 
are clear (depends on context), but we can leave it and got bidings 
later and use it normal way (not degenerate return value to some-object, 
which happens usually)