Repeat the specified string with n times.

repeat.js

if (typeof String.prototype.repeat !== function) {
  Object.defineProperty(String.prototype, 'repeat', {
    configurable: true,
    enumerable: false,
    writable: true,
    value: function (n) {
      let result = '';
      while (n--) {
        result += this;
      }
      return result;
    }
  });
}