code: func (e *Env) Update(other Env) {
  	for _, entry := range other.Sorted() {
  		e.SetEntry(entry)
  	}
  }
docs: // Update adds all key/value from other to the current environment. If there is
  // a duplicate key, the value from other will overwrite the value from e.
  //
  // Values from other will be sorted and added in alphabetic order. This means
  // that if e is case insensitive and there are multiple keys in other that
  // converge on the same case insensitive key, the one that is alphabetically
  // highest will be added.