';'(Disjunction)/2

executes one of two goals.

+Goal1;+Goal2
;(+Goal1,+Goal2)

';'/2 succeeds if Goal1 or Goal2 succeeds. If Goal1 succeeds Goal2 will not be executed. Goal2 will be executed only if Goal1 fails.
By backtracing Goal1 as well as Goal2 can have more than one solution. First Goal1 is backtraced. After finding all solutions of Goal1 Goal2 will be backtraced.
';'/2 is a predefined infix-operator with priority 1100 which is right-associative (see also current_op/3).

Arguments 

Goal1                  goal
Goal2                  goal

Examples

;(integer(2.2), integer(3)). Succeeds.
write(goal1),write(' and goal2'). Succeeds and writes 'goal1'.

Standard

This predicate is part of the ISO-Prolog Standard.

See also

abort/0, break/0, call/1, fcall/1, catch/3, ','(conjunction)/2, '!'(cut)/0, fail/0, true/0, halt/0/1, '->'(if-then)/2, ';'(if-then-else)/2, '\+'(not provable)/1, once/1, repeat/0, throw/1.

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