_apply.js
 1  /**
 2   * A faster alternative to `Function#apply`, this function invokes `func`
 3   * with the `this` binding of `thisArg` and the arguments of `args`.
 4   *
 5   * @private
 6   * @param {Function} func The function to invoke.
 7   * @param {*} thisArg The `this` binding of `func`.
 8   * @param {Array} args The arguments to invoke `func` with.
 9   * @returns {*} Returns the result of `func`.
10   */
11  function apply(func, thisArg, args) {
12    switch (args.length) {
13      case 0: return func.call(thisArg);
14      case 1: return func.call(thisArg, args[0]);
15      case 2: return func.call(thisArg, args[0], args[1]);
16      case 3: return func.call(thisArg, args[0], args[1], args[2]);
17    }
18    return func.apply(thisArg, args);
19  }
20  
21  module.exports = apply;