🚀 go-pugleaf

In article <1162@ttds.UUCP> jonasn@ttds.UUCP (Jonas Nygren) writes:
>When trying to write procedural code for a simple curvplotting routine
>I often encountered problems with backtracking over system-calls. The
>remedy for this was code like:
>	a :- !, b, !, c, !, d, !, e, !.
>to avoid backtracking of goals a,b,c,d,e but this looks rather awkward.

Forgive me, but I cannot imagine this cropping up.  Why do you WANT to
prevent backtracking over system-calls?  You can backtrack over read/1,
write/1, var/1, assert/1 &c all you like, it doesn't hurt.  As a general
rule, code with side-effects should be determinate, so backtracking over
it will do nothing at all.  (retract/1 is an exception, but I doubt that
anyone would commend as an example to follow.)

Please let's see a real example of where you think you need to do this.