Go的切片运动错误

Question

I'm trying to solve the slices exercise. My current solution is

package main

import "golang.org/x/tour/pic"

func Pic(dx, dy int) [][]uint8 {
    picture := make([][]uint8, dy)

    x := dx

    for iy := 0; iy < dy; iy++ {
        picture[iy] = make([]uint8, dx)

        for ix := 0; ix < dx; ix++ {
            x = (x+dy)/2
            picture[iy][ix] = uint8(x)
        }
    }

    return picture
}

func main() {
    pic.Show(Pic(1,2))
}

But I'm getting the following error

tmp/sandbox931798243/main.go:23: cannot use Pic(1, 2) (type [][]uint8) as type func(int, int) [][]uint8 in argument to pic.Show

What am I doing wrong? Might that be a bug with the sandbox?

Answer 1

pic.Show takes a single argument of type func(int, int) [][]uint8 - you need to pass it a function. You're passing the result of executing a func(int, int) [][]uint8, i.e. a [][]uint8. What you want would be:

pic.Show(Pic)

Passing in your function Pic itself, which meets the requirements.