Tour of Go 2.0

Range

Use range to iterate over a slice or map without managing indices yourself.

Each iteration gives you two values: the index, and a copy of the element at that index.

Try it: Change the slice values and see how the loop output updates.

main.go ▶ Run in Playground 
package main

import "fmt"

var pow = []int{1, 2, 4, 8, 16, 32, 64, 128}

func main() {
	for i, v := range pow {
		fmt.Printf("2**%d = %d\n", i, v)
	}
}