function wrapper() {
    // Avoid `arguments` object use disqualifying optimizations by
    // converting it to an array before providing it `func`.
    var argsIndex = -1,
        argsLength = arguments.length,
        leftIndex = -1,
        leftLength = partials.length,
        args = Array(leftLength + argsLength);

    while (++leftIndex < leftLength) {
      args[leftIndex] = partials[leftIndex];
    }
    while (argsLength--) {
      args[leftIndex++] = arguments[++argsIndex];
    }
    var fn = (this && this !== global && this instanceof wrapper) ? Ctor : func;
    return fn.apply(isBind ? thisArg : this, args);
  }
Used as the `TypeError` message for "Functions" methods.