;/2
-- disjunction+*P ;
+*Q
Disjunction: Succeeds if P succeeds or Q succeeds.
This is normally regarded as part of the
syntax of the language, but it is like a built-in predicate in that
you can say call
(P ;
Q). The character |
(vertical bar) can be used as an alternative to ;
.
Note that ;/2
has a distinct behaviour if the first argument
is a ->/2
term. See ;/2
- if-then-else.