For review: Make Mercury cope with impure code (part 2/2)

[Lee Naish]

In article <199711141534.CAA22503 at mundook.cs.mu.OZ.AU>, Fergus Henderson <fjh at cs.mu.oz.au> writes:
> Christopher Rodd SPEIRS, you wrote:
>  > Hi,
>  > 	I was just wondering if I use an impure predicate for a user
>  > defined equality predicate.  Is it allowed?  If so, is it handled
>  > properly?
> 
> A good question.  Fortunately it is one that Peter and I already
> considered.  The answers are "No" and "Yes" respectively.

How about the interaction between impure preds and higher order?  There is
one clause of Peter's code which seems to deal with HO and no mention in
comments/documentation.  My intuition says this is inadequate...

	lee