[m-rev.] diff: reset contains_trace_goal if necessary

[Ralph Becket]

Mark Brown, Thursday,  9 November 2006:
> On 09-Nov-2006, Peter Schachte <schachte at csse.unimelb.edu.au> wrote:
> > On Thu, Nov 09, 2006 at 02:37:44PM +1100, Mark Brown wrote:
> > > An alternative (and
> > > better) way of helping users debug this problem would be to give a warning
> > > whenever a promised pure goal is optimised away.
> > 
> > What's dubious about optimising a promised pure goal away?
> 
> Because the promise might be incorrect, and if it is the result of
> optimising it away can be quite confusing.  Note that if the programmer
> has gone to all the trouble of calling an impure predicate with its
> intended side-effects, and then promises that there are no side-effects,
> I think this is likely to be a bug.

I take it you're referring to impure det code with no outputs?

-- Ralph
--------------------------------------------------------------------------
mercury-reviews mailing list
Post messages to:       mercury-reviews at csse.unimelb.edu.au
Administrative Queries: owner-mercury-reviews at csse.unimelb.edu.au
Subscriptions:          mercury-reviews-request at csse.unimelb.edu.au
--------------------------------------------------------------------------