! Copyright (C) 2008 Doug Coleman. ! See http://factorcode.org/license.txt for BSD license. USING: classes.predicate kernel sequences words ; IN: classes.singleton PREDICATE: singleton-class < predicate-class [ "predicate-definition" word-prop ] [ [ eq? ] curry ] bi sequence= ; : define-singleton-class ( word -- ) \ word over [ eq? ] curry define-predicate-class ;