[pypy-dev] type problems

[Samuele Pedroni]

I agree with this.

At 17:45 07.07.2003 +0200, Michael Hudson wrote:
>I wrote this on the train yesterday.  Some of it is a bit out of date from 
>talking on IRC today, but not all of it.
>
>A tip for making the multimethod implementation more comprehensible: 
>separate finding the method to call from calling it.  Also, consistently 
>using common lisp terminology would help *me*, if no-one else.

it makes sense in general, one problem is that delegation is very specific 
to our multimethods, there is no such notion in CL,Dylan,...


>   And, finally, presuming that the implementation isn't going to change 
> drastically another four or five times, documentation would be good!  As 
> Samuele and Armin are probably too close to write this, perhaps I'll have 
> a stab.  Also, disentangling them from the StdObjSpace implementation (if 
> possible) would probably reduce the general level of incomprehension.
>
>I want a spec for the applicable method computation algorithm -- a 
>sufficiently detailed description to allow implementation by someone 
>unfamiliar with our present one.  I would also like an explanation of why 
>our algorithm is so flaming complicated.

a formal spec for what it happens would be very good indeed. If we cannot 
write it then
we should change the code so that we can write one. If dispatch table 
compression is the way we want to follow it becomes important e.g. to know 
whether our rules are monotonic (table compression algos I know about need 
that) and to reformulate delegation relationships as some kind of subtyping 
rel.

regards.