list? ( object -- ? )

Vocabulary

lists

Inputs and outputs

object	an object
?	a boolean

Word description

Tests if the object is an instance of the list class.

Definition

USING: classes.tuple.private kernel lists.lazy slots.private ;

IN: lists

: list? ( object -- ? )
    dup dup tuple? [
        layout-of
        7
        slot
        dup
        \ lazy-filter
        eq?
        [ drop t ]
        [
            dup \ lazy-until eq?
            [ drop t ] [
                dup \ lazy-while eq?
                [ drop t ] [
                    dup \ lazy-zip eq?
                    [ drop t ] [
                        dup \ lazy-from-by eq?
                        ~quotation~ ~quotation~ if
                    ] if
                ] if
            ] if
        ]
        if
    ] [ drop f ] if [ drop t ] [ +nil+? ] if ;