text-template

Complete the code in line A, to generate content with text template for at most 3 tiers. The expected output is as follows:A B C D 

  1. package main
  3. import (
  4.     "log"
  5.     "os"
  6.     "text/template"
  7. )
  9. func main() {
  10.     const tpl = `
  12. ` // A
  14.     type Tree struct {
  15.         Name     string
  16.         Children []Tree
  17.     }
  18.     root := Tree{
  19.         "A", []Tree{
  20.             Tree{"B", []Tree{
  21.                 Tree{"C", []Tree{}},
  22.             }},
  23.             Tree{"D", []Tree{}},
  24.         },
  25.     }
  27.     t := template.Must(template.New("tree").Parse(tpl))
  29.     err := t.Execute(os.Stdout, root)
  30.     if err != nil {
  31.         log.Fatalf("executing template:", err)
  32.     }
  34. }

Answer

  2. package main
  4. import (
  5.     "log"
  6.     "os"
  7.     "text/template"
  8. )
  10. func main() {
  11.     const tpl = `{{.Name}}{{range $child := .Children}}
  12.  {{$child.Name}}{{range $grandchild := $child.Children}}
  13.   {{$grandchild.Name}}{{end}}{{end}}
  14. ` // A
  16.     type Tree struct {
  17.         Name     string
  18.         Children []Tree
  19.     }
  20.     root := Tree{
  21.         "A", []Tree{
  22.             Tree{"B", []Tree{
  23.                 Tree{"C", []Tree{}},
  24.             }},
  25.             Tree{"D", []Tree{}},
  26.         },
  27.     }
  29.     t := template.Must(template.New("tree").Parse(tpl))
  31.     err := t.Execute(os.Stdout, root)
  32.     if err != nil {
  33.         log.Fatalf("executing template:", err)
  34.     }
  36. }
  38.