1:1 CLASS Widget
  2:3 METHOD describe(mut active: Bool) -> Text
    3:5 IF active
      4:7 LET inner = Widget { active: false }
      5:7 RETURN "on-plain"
    7:5 WHILE active
      8:7 ASSIGN active = false
    10:5 FOR part IN active
      11:7 RETURN "loop"
    13:5 IF Widget { active: true }.active
      14:7 RETURN "on-parenthesized"
    16:5 IF make(Widget { active: true })
      17:7 RETURN "on-call-arg"
    19:5 IF items[Widget { active: true }]
      20:7 RETURN "on-index"
    22:5 LET w = Widget { active: true, label: "hello" }
    23:5 RETURN "off"