How to convert slice to fixed size array?

arrays go slice
thi gg picture thi gg · May 17, 2015 · Viewed 28.4k times · Source

I want to convert a fixed size array from a slice:

func gen(bricks []Brick) {
    if len(bricks) == 16 {
        if check(Sculpture{bricks}) {
            var b [16]Brick = bricks[0:16];
        }
     }
}

But this results in:

 cannot use bricks[0:16] (type []Brick) as type [16]Brick in assignment

How to convert a slice into a fixed size array?

Answer

Stephan Dollberg picture Stephan Dollberg · May 17, 2015

You need to use copy:

slice := []byte("abcdefgh")

var arr [4]byte

copy(arr[:], slice[:4])

fmt.Println(arr)

As Aedolon notes you can also just use

copy(arr[:], slice)

as copy will always only copy the minimum of len(src) and len(dst) bytes.

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