JavaScript enum implementation

JSEnum.js

/**
 * Creates a frozen "enumeration"
 * @see https://masteringjs.io/tutorials/fundamentals/enum
 * @example createEnum(['Up', 'Down', 'Left', 'Right']) returns { Up: 'Up', Down: 'Down', Left: 'Left', Right: 'Right' }
 * @param values Array of items with which to create enum
 * @returns {Readonly<{}>}
 */
export function createEnum(values) {
  const enumObject = {};
  for (const val of values) {
    enumObject[val] = val;
  }
  return Object.freeze(enumObject);
}