[m-dev.] Fw: Re: Impurity annotations on clauses

[Peter Schachte]

Julien Fischer wrote:
> 
> On Tue, 23 Jan 2007, Peter Schachte wrote:
> 
>>>     4) Mode specific clauses (similar to 3).
>>
>> I think of these like foreign code:  they're an opportunity to get the
>> logic
>> wrong, so you should be obliged to certify that you haven't.  I don't see
>> what's wrong with promise_pure for these.
> 
> The problem is that it promises away all the aspects that might cause
> impurity.  In this particular case we already have a pragma,
> promise_equivalent_clauses, that promises away just the impurity due
> to the fact that there are separate clauses.

Good point.  Sounds good.

-- 
Peter Schachte              Don't worry about people stealing your ideas. If
schachte at cs.mu.OZ.AU        your ideas are any good, you'll have to ram them
www.cs.mu.oz.au/~schachte/  down people's throats.
Phone: +61 3 8344 1338          -- Howard Aiken
--------------------------------------------------------------------------
mercury-developers mailing list
Post messages to:       mercury-developers at csse.unimelb.edu.au
Administrative Queries: owner-mercury-developers at csse.unimelb.edu.au
Subscriptions:          mercury-developers-request at csse.unimelb.edu.au
--------------------------------------------------------------------------