Example of use of Golang constant iota

package main
import "fmt"
type color byte
const (
  black color = iota
  red
  blue
)
func test(c color) {
  (c)
}
func main() {
  const (
    x = iota // 0
    y    // 1
    z    // 2
  )
  ("x=%v, y=%v, z=%v\n", x, y, z)
  const (
    _ = iota
    KB = 1 << (10 * iota) // 1 << (10 * 1)
    MB          // 1 << (10 * 2)
    GB          // 1 << (10 * 3)
  )
  ("KB=%v, MB=%v, GB=%v\n", KB, MB, GB)
  const (
    _, _  = iota, iota * 10 // 0, 0 * 10
    aa, bb          // 1, 1 * 10
    cc, dd          // 2, 2 * 10
  )
  ("aa=%v, bb=%v, cc=%v, dd=%v\n", aa, bb, cc, dd)
  const (
    a = iota // 0
    b    // 1
    c = 100 // 100
    d    // 100
    e = iota // 4
    f    // 5
  )
  ("a=%v, b=%v, c=%v, d=%v, e=%v, f=%v\n", a, b, c, d, e, f)
  const (
    g     = iota // 0
    h float32 = iota // 1
    i     = iota // 2
  )
  ("g: %T %v, f: %T %v, h: %T %v\n", g, g, h, h, i, i)
  test(black) // 0
  test(red)  // 1
  test(blue) // 2
  test(100)  // 100 does not exceed the value range of color/byte type  // xx := 2
  // test(xx)
}