singleton-class? ( object -- ? )
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Vocabulary
classes.singleton

Inputs and outputs

object	an object
?	a boolean

Word description
Tests if the object is an instance of the singleton-class class.

Definition

USING: classes.predicate classes.singleton.private kernel
sequences words ;

IN: classes.singleton

: singleton-class? ( object -- ? )
    dup predicate-class? [
        [ "predicate-definition" word-prop ]
        [ singleton-predicate-quot ] bi sequence=
    ] [ drop f ] if ;