Golang range and close channel

Code:

package main

import "golang.org/x/tour/tree"
import "fmt"
// Walk walks the tree t sending all values
// from the tree to the channel ch.
func Walk(t *tree.Tree, ch chan int) {
 if t == nil {
  fmt.Println("Null")
  return
 }
 if t.Left != nil {
  Walk(t.Left, ch)
 }
 ch <- t.Value
 fmt.Println("send ", t.Value)
 if t.Right != nil {
  Walk(t.Right, ch)
 }
}


func main() {
 ta := tree.New(1)
 ca := make(chan int)
 go func() {
  Walk(ta, ca)
  close(ca)
 }()

 for v := range ca {
  fmt.Println("get ", v)
 }
}

Comments:

See which line the channel is closed.