next-step ( grid -- )

Vocabulary

game-of-life

Inputs

grid

an object

Outputs

None

Definition

USING: arrays bit-arrays byte-arrays kernel kernel.private
math.order sequences sequences.private ;

IN: game-of-life

:: next-step ( grid -- )
    grid count-neighbors { array } declare :> neighbors grid
    { array } declare [| row j |
        j neighbors nth-unsafe { byte-array } declare
        :> neighbor-row row { bit-array } declare [| cell i |
            i neighbor-row nth-unsafe cell
            [ 2 3 between? i row set-nth-unsafe ]
            [ 3 = [ t i row set-nth-unsafe ] when ] if
        ] each-index
    ] each-index ;