whole_func_string: function or(first, ...fragments) {
    for (let fragment of fragments) {
      first = orPair(first, fragment);
    }
    return first;
  }
func_code_string: function or(first, ...fragments) {
    for (let fragment of fragments) {
      first = orPair(first, fragment);
    }
    return first;
  }
func_documentation_string: Disjunction factory.
  
  Creates a disjunction NFA for (at least) two NFA-fragments.