text: import { _List } from "./_List"
  
  /*
    Empty List
  */
  
  const Nil = Object.create(_List)
  
  Object.defineProperties(Nil, {
    isEmpty: {
      get() {
        return true
      }
    },
    head: {
      get() {
        throw "head of empty list"
      }
    },
    tail: {
      get() {
        throw "tail of empty list"
      }
    }
  })
  
  export {
    Nil
  }
  