[m-dev.] Re: Visual vs total arity clash example [fwd]

[Ralph Becket]

> From: Fergus Henderson [mailto:fjh at cs.mu.OZ.AU]
> 
> > > Similarly, if the code for that predicate happened to contain
> > > 
> > > 	$x = $y
> > > 
> > > then that expansion would be wrong too.
> > 
> > I don't understand this.
> 
> My point here was that whether `var(x, y)'
> should expand to `T1, T1, T2, T2', as you suggested,
> or `T1, T1, T1, T1' depends on the code in the body
> of the procedure, i.e. neither choice will be right
> for all cases.  Hence I think that for polymorphically
> typed arguments, it is better to have a syntax which makes the type
> parameters explicit, e.g. `var(x(T), y(T))' or 
> `var(x : T, y : T)' or `$~x(T), $~y(T)',
> rather than using a syntax like `var(x, y)'.
> 
> Perhaps the argument above is a bit clearer.

Ah yes.  Hopefully all the major problems have now been
addressed.  The remaining question is whether or not we
should adopt a scheme which requires thread names to be
supplied at call sites.  Obviously, I think we should.
What is the general feeling amongst the rest of the
community?

Cheers,

Ralph
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