[m-dev.] purity of `:- pragma foreign_proc'

[Fergus Henderson]

On 01-Nov-2001, Tyson Dowd <trd at cs.mu.OZ.AU> wrote:
> We also think that it would be nice to have a shortcut so that you don't
> have to write :- pragma promise_pure(...) when you write a foreign_proc.
> 
> Let me collect the syntax proposals together:
> 
> (1) :- pragma pure foreign_proc(...).		% or semipure or impure
> (2) :- pragma promise_pure foreign_proc(...).   % or promise_semipure
> 
> and I'd like to throw in
> 
> (3) :- pragma foreign_proc(..., [promise_pure]). % or promise_semipure

I really don't care.  I could live with any of these.

I could also live with

	(0) No shortcut, so you need to write two declarations:
		:- pragma foreign_proc(..., foo(...), ...).
		:- pragma promise_pure(foo/N).

which has the minor advantage of being easiest to implement.

-- 
Fergus Henderson <fjh at cs.mu.oz.au>  | "... it seems to me that 15 years of
The University of Melbourne         | email is plenty for one lifetime."
WWW: <http://www.cs.mu.oz.au/~fjh>  |     -- Prof. Donald E. Knuth
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