car ( cons -- car )
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Vocabulary
lists

Inputs

cons

a list

Outputs

car	the first item in the list

Word description
Returns the first item in the list.

See also
cdr

Definition

IN: lists

GENERIC: car ( cons -- car )

Methods

USING: circular kernel lists sequences ;

M: circular car 0 swap nth ;


USING: accessors lists ;

M: cons-state car car>> ;


USING: accessors lists lists.lazy ;

M: lazy-append car list1>> car ;


USING: accessors lists lists.lazy ;

M: lazy-concat car car>> car ;


USING: accessors lists lists.lazy promises ;

M: lazy-cons-state car car>> force ;


USING: accessors kernel lists lists.lazy lists.lazy.private ;

M: lazy-filter car
    dup car-filtered? [ cons>> ] [ skip ] if car ;


USING: accessors lists lists.lazy ;

M: lazy-from-by car n>> ;


USING: accessors combinators kernel lists lists.lazy ;

M: lazy-io car
    dup car>>
    [ nip ] [
        dup [ stream>> ] [ quot>> ] bi
        ( stream -- value ) call-effect
        [ >>car ] [ drop nil ] if*
    ] if* ;


USING: accessors combinators kernel lists lists.lazy ;

M: lazy-map car
    [ cons>> car ] [ quot>> ( old -- new ) call-effect ] bi ;


USING: accessors lists lists.lazy ;

M: lazy-take car cons>> car ;


USING: accessors lists lists.lazy ;

M: lazy-until car cons>> car ;


USING: accessors lists lists.lazy ;

M: lazy-while car cons>> car ;


USING: accessors arrays kernel lists lists.lazy ;

M: lazy-zip car [ list1>> car ] keep list2>> car 2array ;


USING: accessors kernel lists lists.lazy ;

M: memoized-cons car
    dup car>> +not-memoized+ eq?
    [ dup original>> car [ >>car drop ] keep ] [ car>> ] if ;


USING: lists promises ;

M: promise car force car ;


USING: accessors kernel lists lists.lazy sequences ;

M: sequence-cons car [ index>> ] [ seq>> nth ] bi ;