code: function (key, base) {                                                                            // 477
    if ((typeof key) === "number" || key.match(/^[0-9]+$/))                                                            // 478
      key = "[" + key + "]";                                                                                           // 479
    else if (!key.match(/^[a-z_$][0-9a-z_$]*$/i) || _.contains(_jsKeywords, key))                                      // 480
      key = JSON.stringify([key]);                                                                                     // 481
                                                                                                                       // 482
    if (base && base[0] !== "[")                                                                                       // 483
      return key + '.' + base;                                                                                         // 484
    return key + base;                                                                                                 // 485
  }
docs: 473 474 Assumes the base of path is already escaped properly                                                              // 475 returns key + base                                                                                                // 476