[m-dev.] diff: list__foldl2

[Tyson Richard DOWD]

> > +:- pred list__foldl2(pred(X, Y, Y, Z, Z), list(X), Y, Y, Z, Z).
> > +:- mode list__foldl2(pred(in, in, out, in, out) is det,
> > +		in, in, out, in, out) is det.
> > +:- mode list__foldl2(pred(in, in, out, di, uo) is det,
> > +		in, in, out, di, uo) is det.
> 
> How about:
> 	:- mode list__foldl2(pred(in, in, out, di, uo) is det,
> 		in, di, uo, di, uo) is det.
> ?

I'd rather not introduce a mode error into the library, thanks ;-)

However, this
 	:- mode list__foldl2(pred(in, di, uo, di, uo) is det,
 		in, di, uo, di, uo) is det.

would work. I'll add that one because it's probably useful. I don't
think many other modes (eg semidet pred) would be particularly useful.
We can add them later if the are.

-- 
       Tyson Dowd           # 
                            #  Surreal humour isn't eveyone's cup of
     trd at cs.mu.oz.au        #  fur.
http://www.cs.mu.oz.au/~trd #