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