25 lines
761 B
Factor
25 lines
761 B
Factor
! Copyright (C) 2004, 2007 Slava Pestov.
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! See http://factorcode.org/license.txt for BSD license.
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USING: classes kernel namespaces words ;
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IN: classes.predicate
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PREDICATE: class predicate-class
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"metaclass" word-prop predicate-class eq? ;
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: predicate-quot ( class -- quot )
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[
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\ dup ,
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dup superclass "predicate" word-prop %
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"predicate-definition" word-prop , [ drop f ] , \ if ,
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] [ ] make ;
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: define-predicate-class ( superclass class definition -- )
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>r dup f roll predicate-class define-class r>
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dupd "predicate-definition" set-word-prop
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dup predicate-word over predicate-quot define-predicate ;
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M: predicate-class reset-class
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{
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"metaclass" "predicate-definition" "superclass"
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} reset-props ;
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