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1/**
2 * lodash 3.6.1 (Custom Build) <https://lodash.com/>
3 * Build: `lodash modern modularize exports="npm" -o ./`
4 * Copyright 2012-2015 The Dojo Foundation <http://dojofoundation.org/>
5 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
6 * Copyright 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
7 * Available under MIT license <https://lodash.com/license>
8 */
9
10/** Used as the `TypeError` message for "Functions" methods. */
11var FUNC_ERROR_TEXT = 'Expected a function';
12
13/* Native method references for those with the same name as other `lodash` methods. */
14var nativeMax = Math.max;
15
16/**
17 * Creates a function that invokes `func` with the `this` binding of the
18 * created function and arguments from `start` and beyond provided as an array.
19 *
20 * **Note:** This method is based on the [rest parameter](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters).
21 *
22 * @static
23 * @memberOf _
24 * @category Function
25 * @param {Function} func The function to apply a rest parameter to.
26 * @param {number} [start=func.length-1] The start position of the rest parameter.
27 * @returns {Function} Returns the new function.
28 * @example
29 *
30 * var say = _.restParam(function(what, names) {
31 *   return what + ' ' + _.initial(names).join(', ') +
32 *     (_.size(names) > 1 ? ', & ' : '') + _.last(names);
33 * });
34 *
35 * say('hello', 'fred', 'barney', 'pebbles');
36 * // => 'hello fred, barney, & pebbles'
37 */
38function restParam(func, start) {
39  if (typeof func != 'function') {
40    throw new TypeError(FUNC_ERROR_TEXT);
41  }
42  start = nativeMax(start === undefined ? (func.length - 1) : (+start || 0), 0);
43  return function() {
44    var args = arguments,
45        index = -1,
46        length = nativeMax(args.length - start, 0),
47        rest = Array(length);
48
49    while (++index < length) {
50      rest[index] = args[start + index];
51    }
52    switch (start) {
53      case 0: return func.call(this, rest);
54      case 1: return func.call(this, args[0], rest);
55      case 2: return func.call(this, args[0], args[1], rest);
56    }
57    var otherArgs = Array(start + 1);
58    index = -1;
59    while (++index < start) {
60      otherArgs[index] = args[index];
61    }
62    otherArgs[start] = rest;
63    return func.apply(this, otherArgs);
64  };
65}
66
67module.exports = restParam;
68