jimc@ukc.UUCP (J.A.Crammond) (08/25/83)
We have Prolog-10 version 3 running on our DEC-10 and I was testing
out the \+ evaluable predicate seeing whether the clause "\+(member(X,L)"
was any faster than an explicit "not_member(X,L)" in a program I had written.
Below are the approximate runtimes of the incore compiler and interpreter
running this program. (NB I was the only user on the system at the time).
interpreter compile
not_member(X,L) 2+23 8+4
\+(member(X,L)) 2+22 8+158
The time X+Y indicates "compile time"+"execute time" in seconds.
Clearly the compiler is doing some thing VERY odd with \+(P).
Any one come across this before?
Jim Crammond, Leeds University.