[MLton] List comprehensions?

[skaller]

On Thu, 2007-05-31 at 15:57 +0200, Wesley W. Terpstra wrote:

> This feature will probably break MLton's defunctorization, though:
> > * Local Modules.
> >
> >   Structure, functor and signature declarations are allowed in  
> > local scope:

> I have needed this feature in the past, but what does this mean for  
> 'val's declared in the functor? Must they be evaluated every time the  
> function is called? I think so. They might depend on the parameter.

They're evaluated every time the function elaborates the functor.

Local modules .. including functors .. are available in Ocaml now.

> I think that the equality type is an ugly wart in SML. Plus, haskell  
> shows just how flexible type classes can be. In particular, the a..b  
> notation in Haskell is an elegant example of how great type classes  
> are. Similarly, the List.map, Vector.map, ... show redundancy that so  
> cleanly fits this paradigm that it's almost embarrassing it's absent.

IMHO, typeclasses are a wart. It's a hack to make up for
real polyadic programming.

-- 
John Skaller <skaller at users dot sf dot net>
Felix, successor to C++: http://felix.sf.net