[m-dev.] polymorphic modes

[Fergus Henderson]

On 09-Feb-2000, Robert Ernst Johann JESCHOFNIK <rejj at students.cs.mu.oz.au> wrote:
> On Wed, 9 Feb 2000, David Overton wrote:
> 
> > > What happens if you call p/1 with a arguments whose
> > > initial insts are `(unique, free)'?  Does that end
> > > up calling the `p(in(ground), out(ground))' mode,
> > > or is it a mode error?
> > > 
> > 
> > The former.
> 
> Is this desireable?

Yes.

> I think at the very least there should be a warning, letting you know that
> the uniqueness has been slaughtered.

That would lead to a lot of spurious warnings...
E.g. for `p(1, X)', the initial inst of the first
argument is `unique(1)'; if the compiler is going to warn
every time some potential uniqueness is ignored,
then you will end up with a LOT of warnings.

-- 
Fergus Henderson <fjh at cs.mu.oz.au>  |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>  |  of excellence is a lethal habit"
PGP: finger fjh at 128.250.37.3        |     -- the last words of T. S. Garp.
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