Why doesn't gnu prolog support the "false" predicate? (I've changed to swi)

Question

I've been using the gprolog thingy to do some things in prolog. But now when testing some more code I discovered that it does not support "false". Which is supported by swi?

Answer 1

Use fail instead of false. I believe the former is in the ISO standard for Prolog. Otherwise, define it yourself:

false :- 0=1.

or

fail :- 0=1.

Answer 2

Recent versions of GNU Prolog (1.4.0) do support false/0.

false/0 is not defined in the original ISO standard of 1995, but is part of Cor.2:2012.