tour:explanation for "For is Go's "while"" is not enough!

[Mehdi-orang]

I don't know below code how computing the out!! https://tour.golang.org/flowcontrol/3

package main

import "fmt"

func main() { sum := 1 for sum < 9 { sum += sum } fmt.Println(sum) }

[ghost]

Try something like this?

 package main

 import "fmt"

 func main() {
    sum := 1
    for sum < 9 {
+       fmt.Println(sum)
        sum += sum
    }
    fmt.Println(sum)
 }