true/0

succeeds exactly once.

true/0

true/0 succeeds exactly once.

Examples

write('this is going to succeed'), true. Succeeds with output on the current outputstream
'this is going to succeed'.
integer(a),true. Fails.

Standard

This predicate is part of the ISO-Prolog Standard.

See also

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

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