🚀 go-pugleaf

This is an excerpt from an article posted recently to another newsgroup:

| > the most frequently occuring construct in any programming language is
| > equivalent to the construct x += 1
| 
| Er, not quite *any* programming language.  I have been programming
| professionally in Prolog for the last five years, and I need to do
| this sort of thing maybe once or twice a year.
| 
| BTW, here's how to do it:
| 
| 	increment(Variable) :-
| 		retract(value(Variable, OldValue)),
| 		NewValue is OldValue + 1,
| 		assert(value(Variable, NewValue)).
| 
| 	..., increment(x), ...
| 
| but as this makes two modifications to the database and is therefore
| pretty expensive (not to mention poor style), you don't want to do it
| too often.

Comments?
-- 
Saumya Debray		CS Department, University of Arizona, Tucson

     internet:   debray@cs.arizona.edu
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