instance? ( object class -- ? )
Factor handbook » The language » Objects » Classes

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Vocabulary
classes

Inputs

object	an object
class	a class

Outputs

?

a boolean

Word description
Tests whether the input object is a member of the class.

Definition

IN: classes

GENERIC: instance? ( object class -- ? ) flushable

Methods

USING: accessors classes classes.algebra.private kernel ;

M: anonymous-complement instance?
    over [ class>> instance? not ] [ 2drop t ] if ;


USING: accessors classes classes.algebra.private kernel
sequences ;

M: anonymous-intersection instance?
    participants>> [ instance? ] with all? ;


USING: accessors classes classes.algebra.private combinators
kernel ;

M: anonymous-predicate instance?
    2dup class>> instance?
    [ predicate>> ( object -- ? ) call-effect ] [ 2drop f ] if ;


USING: accessors classes classes.algebra.private kernel
sequences ;

M: anonymous-union instance? members>> [ instance? ] with any? ;


USING: classes classes.builtin kernel kernel.private ;

M: builtin-class instance? [ tag ] [ class>type ] bi* eq? ;


USING: classes classes.intersection kernel sequences words ;

M: intersection-class instance?
    "participants" word-prop [ instance? ] with all? ;


USING: accessors classes classes.maybe kernel ;

M: maybe instance? over [ class>> instance? ] [ 2drop t ] if ;


USING: classes classes.predicate combinators kernel words ;

M: predicate-class instance?
    2dup superclass-of instance? [
        "predicate-definition" word-prop
        ( object -- ? ) call-effect
    ] [ 2drop f ] if ;


USING: classes classes.singleton kernel ;

M: singleton-class instance? eq? ;


USING: classes classes.tuple classes.tuple.private kernel ;

M: tuple-class instance?
    dup echelon-of layout-class-offset tuple-instance? ;


USING: classes classes.union kernel sequences words ;

M: union-class instance?
    "members" word-prop [ instance? ] with any? ;