text: /*
   *  @license
   *    Copyright 2017 Brigham Young University
   *
   *    Licensed under the Apache License, Version 2.0 (the "License");
   *    you may not use this file except in compliance with the License.
   *    You may obtain a copy of the License at
   *
   *        http://www.apache.org/licenses/LICENSE-2.0
   *
   *    Unless required by applicable law or agreed to in writing, software
   *    distributed under the License is distributed on an "AS IS" BASIS,
   *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *    See the License for the specific language governing permissions and
   *    limitations under the License.
   */
  
  "use strict";
  
  module.exports = {
  
      isSuperset(set, subset) {
          for (let elem of subset) {
              if (!set.has(elem)) {
                  return false;
              }
          }
          return true;
      },
  
      union(set, other) {
          let union = new Set(set);
          for (let e of other) {
              union.add(e);
          }
          return union;
      },
  
      intersection(set, other) {
          let inter = new Set();
          for (let e of other) {
              if (set.has(e)) {
                  inter.add(e);
              }
          }
          return inter;
      },
  
      difference(set, other) {
          let diff = new Set(set);
          for (let e of other) {
              diff.delete(e);
          }
          return diff;
      },
  
  };
  
  