Node:ISO Compliance, Previous:Function Prototypes, Up:Notation

ISO Compliance

SICStus Prolog provides two execution modes: the iso mode, which is fully compliant with the International Standard ISO/IEC 13211-1 (PROLOG: Part 1--General Core) (; and the sicstus mode, which supports code written in earlier versions of SICStus Prolog. The execution mode can be changed using the Prolog flag language; see State Info. Note, however, that SICStus Prolog does not offer a strictly conforming mode that rejects uses of implementation specific features.

To aid programmers who wish to write standard compliant programs, built-in predicates that are part of the ISO Prolog Standard are annotated with [ISO] in this manual. If such a predicate behaves differently in sicstus mode, an appropriate clarification is given. For the few predicates that have a completely different meaning in the two modes, two separate descriptions are given. The one for the iso mode is annotated with [ISO only], while the sicstus mode version is annotated with [SICStus only].