type inference for python

[Philippe Fremy <pfremy@inseal.com>]

	Hi,

I would like to implement something similar to the type inference of 
ocaml for the python language. I have always found it very impressive 
(although I have only used caml light).

I have no experience with the topic, it is just a project that seems 
cool to me :-)

Do you have any hints or where I could build up my knowledge (code, 
books, article, ...) to do that kind of thing.

I imagine that it works in a kind of three way pass:

1. analyse all the constraints of the code
Ex:
def f(a): a.append(1)
def g(a): a=a+1; f(a)
g('coucou')

=> a must support append
=> a must also be an int

2. cross-validate the constraints consistency
=> inconsistent assertions

3. validate the constraints against reality
=> g('coucou') will not work


The 2. and 3. looks like the most difficult aspect of it.

	regards,

	Philippe

-- 
Philippe Fremy
InSeal Technical Director
tel: +33 6 07 98 76 44