Bump to v3.8.0.

README.md

@@ -1,4 +1,4 @@
-# lodash v3.4.0
+# lodash v3.8.0
 
 The [modern build](https://github.com/lodash/lodash/wiki/Build-Differences) of [lodash](https://lodash.com/) exported as [AMD](https://github.com/amdjs/amdjs-api/wiki/AMD) modules.
 
@@ -10,6 +10,13 @@ $ lodash modern exports=amd -d -o ./main.js
 
 ## Installation
 
+Using bower or volo:
+
+```bash
+$ bower i lodash#3.8.0-amd
+$ volo add lodash/3.8.0-amd
+```
+
 Defining a build as `'lodash'`.
 
 ```js

array.js

@@ -1,4 +1,4 @@
-define(['./array/chunk', './array/compact', './array/difference', './array/drop', './array/dropRight', './array/dropRightWhile', './array/dropWhile', './array/fill', './array/findIndex', './array/findLastIndex', './array/first', './array/flatten', './array/flattenDeep', './array/head', './array/indexOf', './array/initial', './array/intersection', './array/last', './array/lastIndexOf', './array/object', './array/pull', './array/pullAt', './array/remove', './array/rest', './array/slice', './array/sortedIndex', './array/sortedLastIndex', './array/tail', './array/take', './array/takeRight', './array/takeRightWhile', './array/takeWhile', './array/union', './array/uniq', './array/unique', './array/unzip', './array/without', './array/xor', './array/zip', './array/zipObject'], function(chunk, compact, difference, drop, dropRight, dropRightWhile, dropWhile, fill, findIndex, findLastIndex, first, flatten, flattenDeep, head, indexOf, initial, intersection, last, lastIndexOf, object, pull, pullAt, remove, rest, slice, sortedIndex, sortedLastIndex, tail, take, takeRight, takeRightWhile, takeWhile, union, uniq, unique, unzip, without, xor, zip, zipObject) {
+define(['./array/chunk', './array/compact', './array/difference', './array/drop', './array/dropRight', './array/dropRightWhile', './array/dropWhile', './array/fill', './array/findIndex', './array/findLastIndex', './array/first', './array/flatten', './array/flattenDeep', './array/head', './array/indexOf', './array/initial', './array/intersection', './array/last', './array/lastIndexOf', './array/object', './array/pull', './array/pullAt', './array/remove', './array/rest', './array/slice', './array/sortedIndex', './array/sortedLastIndex', './array/tail', './array/take', './array/takeRight', './array/takeRightWhile', './array/takeWhile', './array/union', './array/uniq', './array/unique', './array/unzip', './array/unzipWith', './array/without', './array/xor', './array/zip', './array/zipObject', './array/zipWith'], function(chunk, compact, difference, drop, dropRight, dropRightWhile, dropWhile, fill, findIndex, findLastIndex, first, flatten, flattenDeep, head, indexOf, initial, intersection, last, lastIndexOf, object, pull, pullAt, remove, rest, slice, sortedIndex, sortedLastIndex, tail, take, takeRight, takeRightWhile, takeWhile, union, uniq, unique, unzip, unzipWith, without, xor, zip, zipObject, zipWith) {
   return {
     'chunk': chunk,
     'compact': compact,
@@ -36,9 +36,11 @@ define(['./array/chunk', './array/compact', './array/difference', './array/drop'
     'uniq': uniq,
     'unique': unique,
     'unzip': unzip,
+    'unzipWith': unzipWith,
     'without': without,
     'xor': xor,
     'zip': zip,
-    'zipObject': zipObject
+    'zipObject': zipObject,
+    'zipWith': zipWith
   };
 });

array/difference.js

@@ -1,13 +1,9 @@
-define(['../internal/baseDifference', '../internal/baseFlatten', '../lang/isArguments', '../lang/isArray'], function(baseDifference, baseFlatten, isArguments, isArray) {
+define(['../internal/baseDifference', '../internal/baseFlatten', '../internal/isArrayLike', '../function/restParam'], function(baseDifference, baseFlatten, isArrayLike, restParam) {
 
   /**
    * Creates an array excluding all values of the provided arrays using
-   * `SameValueZero` for equality comparisons.
-   *
-   * **Note:** `SameValueZero` comparisons are like strict equality comparisons,
-   * e.g. `===`, except that `NaN` matches `NaN`. See the
-   * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
-   * for more details.
+   * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+   * for equality comparisons.
    *
    * @static
    * @memberOf _
@@ -20,19 +16,11 @@ define(['../internal/baseDifference', '../internal/baseFlatten', '../lang/isArgu
    * _.difference([1, 2, 3], [4, 2]);
    * // => [1, 3]
    */
-  function difference() {
-    var args = arguments,
-        index = -1,
-        length = args.length;
-
-    while (++index < length) {
-      var value = args[index];
-      if (isArray(value) || isArguments(value)) {
-        break;
-      }
-    }
-    return baseDifference(value, baseFlatten(args, false, true, ++index));
-  }
+  var difference = restParam(function(array, values) {
+    return isArrayLike(array)
+      ? baseDifference(array, baseFlatten(values, false, true))
+      : [];
+  });
 
   return difference;
 });

array/dropRightWhile.js

@@ -1,9 +1,9 @@
-define(['../internal/baseCallback', '../internal/baseSlice'], function(baseCallback, baseSlice) {
+define(['../internal/baseCallback', '../internal/baseWhile'], function(baseCallback, baseWhile) {
 
   /**
    * Creates a slice of `array` excluding elements dropped from the end.
    * Elements are dropped until `predicate` returns falsey. The predicate is
-   * bound to `thisArg` and invoked with three arguments; (value, index, array).
+   * bound to `thisArg` and invoked with three arguments: (value, index, array).
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.
@@ -50,13 +50,9 @@ define(['../internal/baseCallback', '../internal/baseSlice'], function(baseCallb
    * // => ['barney', 'fred', 'pebbles']
    */
   function dropRightWhile(array, predicate, thisArg) {
-    var length = array ? array.length : 0;
-    if (!length) {
-      return [];
-    }
-    predicate = baseCallback(predicate, thisArg, 3);
-    while (length-- && predicate(array[length], length, array)) {}
-    return baseSlice(array, 0, length + 1);
+    return (array && array.length)
+      ? baseWhile(array, baseCallback(predicate, thisArg, 3), true, true)
+      : [];
   }
 
   return dropRightWhile;

array/dropWhile.js

@@ -1,9 +1,9 @@
-define(['../internal/baseCallback', '../internal/baseSlice'], function(baseCallback, baseSlice) {
+define(['../internal/baseCallback', '../internal/baseWhile'], function(baseCallback, baseWhile) {
 
   /**
    * Creates a slice of `array` excluding elements dropped from the beginning.
    * Elements are dropped until `predicate` returns falsey. The predicate is
-   * bound to `thisArg` and invoked with three arguments; (value, index, array).
+   * bound to `thisArg` and invoked with three arguments: (value, index, array).
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.
@@ -50,14 +50,9 @@ define(['../internal/baseCallback', '../internal/baseSlice'], function(baseCallb
    * // => ['barney', 'fred', 'pebbles']
    */
   function dropWhile(array, predicate, thisArg) {
-    var length = array ? array.length : 0;
-    if (!length) {
-      return [];
-    }
-    var index = -1;
-    predicate = baseCallback(predicate, thisArg, 3);
-    while (++index < length && predicate(array[index], index, array)) {}
-    return baseSlice(array, index);
+    return (array && array.length)
+      ? baseWhile(array, baseCallback(predicate, thisArg, 3), true)
+      : [];
   }
 
   return dropWhile;

array/fill.js

@@ -14,6 +14,19 @@ define(['../internal/baseFill', '../internal/isIterateeCall'], function(baseFill
    * @param {number} [start=0] The start position.
    * @param {number} [end=array.length] The end position.
    * @returns {Array} Returns `array`.
+   * @example
+   *
+   * var array = [1, 2, 3];
+   *
+   * _.fill(array, 'a');
+   * console.log(array);
+   * // => ['a', 'a', 'a']
+   *
+   * _.fill(Array(3), 2);
+   * // => [2, 2, 2]
+   *
+   * _.fill([4, 6, 8], '*', 1, 2);
+   * // => [4, '*', 8]
    */
   function fill(array, value, start, end) {
     var length = array ? array.length : 0;

array/findIndex.js

@@ -1,8 +1,8 @@
-define(['../internal/baseCallback'], function(baseCallback) {
+define(['../internal/createFindIndex'], function(createFindIndex) {
 
   /**
    * This method is like `_.find` except that it returns the index of the first
-   * element `predicate` returns truthy for, instead of the element itself.
+   * element `predicate` returns truthy for instead of the element itself.
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.
@@ -48,18 +48,7 @@ define(['../internal/baseCallback'], function(baseCallback) {
    * _.findIndex(users, 'active');
    * // => 2
    */
-  function findIndex(array, predicate, thisArg) {
-    var index = -1,
-        length = array ? array.length : 0;
-
-    predicate = baseCallback(predicate, thisArg, 3);
-    while (++index < length) {
-      if (predicate(array[index], index, array)) {
-        return index;
-      }
-    }
-    return -1;
-  }
+  var findIndex = createFindIndex();
 
   return findIndex;
 });

array/findLastIndex.js

@@ -1,4 +1,4 @@
-define(['../internal/baseCallback'], function(baseCallback) {
+define(['../internal/createFindIndex'], function(createFindIndex) {
 
   /**
    * This method is like `_.findIndex` except that it iterates over elements
@@ -48,16 +48,7 @@ define(['../internal/baseCallback'], function(baseCallback) {
    * _.findLastIndex(users, 'active');
    * // => 0
    */
-  function findLastIndex(array, predicate, thisArg) {
-    var length = array ? array.length : 0;
-    predicate = baseCallback(predicate, thisArg, 3);
-    while (length--) {
-      if (predicate(array[length], length, array)) {
-        return length;
-      }
-    }
-    return -1;
-  }
+  var findLastIndex = createFindIndex(true);
 
   return findLastIndex;
 });

array/flatten.js

@@ -14,18 +14,18 @@ define(['../internal/baseFlatten', '../internal/isIterateeCall'], function(baseF
    * @example
    *
    * _.flatten([1, [2, 3, [4]]]);
-   * // => [1, 2, 3, [4]];
+   * // => [1, 2, 3, [4]]
    *
    * // using `isDeep`
    * _.flatten([1, [2, 3, [4]]], true);
-   * // => [1, 2, 3, 4];
+   * // => [1, 2, 3, 4]
    */
   function flatten(array, isDeep, guard) {
     var length = array ? array.length : 0;
     if (guard && isIterateeCall(array, isDeep, guard)) {
       isDeep = false;
     }
-    return length ? baseFlatten(array, isDeep, false, 0) : [];
+    return length ? baseFlatten(array, isDeep) : [];
   }
 
   return flatten;

array/flattenDeep.js

@@ -11,11 +11,11 @@ define(['../internal/baseFlatten'], function(baseFlatten) {
    * @example
    *
    * _.flattenDeep([1, [2, 3, [4]]]);
-   * // => [1, 2, 3, 4];
+   * // => [1, 2, 3, 4]
    */
   function flattenDeep(array) {
     var length = array ? array.length : 0;
-    return length ? baseFlatten(array, true, false, 0) : [];
+    return length ? baseFlatten(array, true) : [];
   }
 
   return flattenDeep;

array/indexOf.js

@@ -5,14 +5,10 @@ define(['../internal/baseIndexOf', '../internal/binaryIndex'], function(baseInde
 
   /**
    * Gets the index at which the first occurrence of `value` is found in `array`
-   * using `SameValueZero` for equality comparisons. If `fromIndex` is negative,
-   * it is used as the offset from the end of `array`. If `array` is sorted
-   * providing `true` for `fromIndex` performs a faster binary search.
-   *
-   * **Note:** `SameValueZero` comparisons are like strict equality comparisons,
-   * e.g. `===`, except that `NaN` matches `NaN`. See the
-   * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
-   * for more details.
+   * using [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+   * for equality comparisons. If `fromIndex` is negative, it is used as the offset
+   * from the end of `array`. If `array` is sorted providing `true` for `fromIndex`
+   * performs a faster binary search.
    *
    * @static
    * @memberOf _
@@ -46,7 +42,10 @@ define(['../internal/baseIndexOf', '../internal/binaryIndex'], function(baseInde
       var index = binaryIndex(array, value),
           other = array[index];
 
-      return (value === value ? value === other : other !== other) ? index : -1;
+      if (value === value ? (value === other) : (other !== other)) {
+        return index;
+      }
+      return -1;
     }
     return baseIndexOf(array, value, fromIndex || 0);
   }

array/intersection.js

@@ -1,14 +1,10 @@
-define(['../internal/baseIndexOf', '../internal/cacheIndexOf', '../internal/createCache', '../lang/isArguments', '../lang/isArray'], function(baseIndexOf, cacheIndexOf, createCache, isArguments, isArray) {
+define(['../internal/baseIndexOf', '../internal/cacheIndexOf', '../internal/createCache', '../internal/isArrayLike'], function(baseIndexOf, cacheIndexOf, createCache, isArrayLike) {
 
   /**
-   * Creates an array of unique values in all provided arrays using `SameValueZero`
+   * Creates an array of unique values in all provided arrays using
+   * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
    * for equality comparisons.
    *
-   * **Note:** `SameValueZero` comparisons are like strict equality comparisons,
-   * e.g. `===`, except that `NaN` matches `NaN`. See the
-   * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
-   * for more details.
-   *
    * @static
    * @memberOf _
    * @category Array
@@ -24,20 +20,23 @@ define(['../internal/baseIndexOf', '../internal/cacheIndexOf', '../internal/crea
         argsLength = arguments.length,
         caches = [],
         indexOf = baseIndexOf,
-        isCommon = true;
+        isCommon = true,
+        result = [];
 
     while (++argsIndex < argsLength) {
       var value = arguments[argsIndex];
-      if (isArray(value) || isArguments(value)) {
+      if (isArrayLike(value)) {
         args.push(value);
         caches.push((isCommon && value.length >= 120) ? createCache(argsIndex && value) : null);
       }
     }
     argsLength = args.length;
+    if (argsLength < 2) {
+      return result;
+    }
     var array = args[0],
         index = -1,
         length = array ? array.length : 0,
-        result = [],
         seen = caches[0];
 
     outer:

array/lastIndexOf.js

@@ -40,7 +40,10 @@ define(['../internal/binaryIndex', '../internal/indexOfNaN'], function(binaryInd
     } else if (fromIndex) {
       index = binaryIndex(array, value, true) - 1;
       var other = array[index];
-      return (value === value ? value === other : other !== other) ? index : -1;
+      if (value === value ? (value === other) : (other !== other)) {
+        return index;
+      }
+      return -1;
     }
     if (value !== value) {
       return indexOfNaN(array, index, true);

array/pull.js

@@ -7,14 +7,11 @@ define(['../internal/baseIndexOf'], function(baseIndexOf) {
   var splice = arrayProto.splice;
 
   /**
-   * Removes all provided values from `array` using `SameValueZero` for equality
-   * comparisons.
+   * Removes all provided values from `array` using
+   * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+   * for equality comparisons.
    *
-   * **Notes:**
-   *  - Unlike `_.without`, this method mutates `array`.
-   *  - `SameValueZero` comparisons are like strict equality comparisons, e.g. `===`,
-   *    except that `NaN` matches `NaN`. See the [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
-   *    for more details.
+   * **Note:** Unlike `_.without`, this method mutates `array`.
    *
    * @static
    * @memberOf _

array/pullAt.js

@@ -1,4 +1,4 @@
-define(['../internal/baseFlatten', '../internal/basePullAt'], function(baseFlatten, basePullAt) {
+define(['../internal/baseAt', '../internal/baseCompareAscending', '../internal/baseFlatten', '../internal/basePullAt', '../function/restParam'], function(baseAt, baseCompareAscending, baseFlatten, basePullAt, restParam) {
 
   /**
    * Removes elements from `array` corresponding to the given indexes and returns
@@ -25,9 +25,13 @@ define(['../internal/baseFlatten', '../internal/basePullAt'], function(baseFlatt
    * console.log(evens);
    * // => [10, 20]
    */
-  function pullAt(array) {
-    return basePullAt(array || [], baseFlatten(arguments, false, false, 1));
-  }
+  var pullAt = restParam(function(array, indexes) {
+    indexes = baseFlatten(indexes);
+
+    var result = baseAt(array, indexes);
+    basePullAt(array, indexes.sort(baseCompareAscending));
+    return result;
+  });
 
   return pullAt;
 });

array/remove.js

@@ -1,15 +1,9 @@
-define(['../internal/baseCallback'], function(baseCallback) {
-
-  /** Used for native method references. */
-  var arrayProto = Array.prototype;
-
-  /** Native method references. */
-  var splice = arrayProto.splice;
+define(['../internal/baseCallback', '../internal/basePullAt'], function(baseCallback, basePullAt) {
 
   /**
    * Removes all elements from `array` that `predicate` returns truthy for
    * and returns an array of the removed elements. The predicate is bound to
-   * `thisArg` and invoked with three arguments; (value, index, array).
+   * `thisArg` and invoked with three arguments: (value, index, array).
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.
@@ -46,19 +40,23 @@ define(['../internal/baseCallback'], function(baseCallback) {
    * // => [2, 4]
    */
   function remove(array, predicate, thisArg) {
+    var result = [];
+    if (!(array && array.length)) {
+      return result;
+    }
     var index = -1,
-        length = array ? array.length : 0,
-        result = [];
+        indexes = [],
+        length = array.length;
 
     predicate = baseCallback(predicate, thisArg, 3);
     while (++index < length) {
       var value = array[index];
       if (predicate(value, index, array)) {
         result.push(value);
-        splice.call(array, index--, 1);
-        length--;
+        indexes.push(index);
       }
     }
+    basePullAt(array, indexes);
     return result;
   }
 

array/slice.js

@@ -3,7 +3,7 @@ define(['../internal/baseSlice', '../internal/isIterateeCall'], function(baseSli
   /**
    * Creates a slice of `array` from `start` up to, but not including, `end`.
    *
-   * **Note:** This function is used instead of `Array#slice` to support node
+   * **Note:** This method is used instead of `Array#slice` to support node
    * lists in IE < 9 and to ensure dense arrays are returned.
    *
    * @static

array/sortedIndex.js

@@ -1,4 +1,4 @@
-define(['../internal/baseCallback', '../internal/binaryIndex', '../internal/binaryIndexBy'], function(baseCallback, binaryIndex, binaryIndexBy) {
+define(['../internal/createSortedIndex'], function(createSortedIndex) {
 
   /**
    * Uses a binary search to determine the lowest index at which `value` should
@@ -7,14 +7,14 @@ define(['../internal/baseCallback', '../internal/binaryIndex', '../internal/bina
    * to compute their sort ranking. The iteratee is bound to `thisArg` and
    * invoked with one argument; (value).
    *
-   * If a property name is provided for `predicate` the created `_.property`
+   * If a property name is provided for `iteratee` the created `_.property`
    * style callback returns the property value of the given element.
    *
    * If a value is also provided for `thisArg` the created `_.matchesProperty`
    * style callback returns `true` for elements that have a matching property
    * value, else `false`.
    *
-   * If an object is provided for `predicate` the created `_.matches` style
+   * If an object is provided for `iteratee` the created `_.matches` style
    * callback returns `true` for elements that have the properties of the given
    * object, else `false`.
    *
@@ -48,11 +48,7 @@ define(['../internal/baseCallback', '../internal/binaryIndex', '../internal/bina
    * _.sortedIndex([{ 'x': 30 }, { 'x': 50 }], { 'x': 40 }, 'x');
    * // => 1
    */
-  function sortedIndex(array, value, iteratee, thisArg) {
-    return iteratee == null
-      ? binaryIndex(array, value)
-      : binaryIndexBy(array, value, baseCallback(iteratee, thisArg, 1));
-  }
+  var sortedIndex = createSortedIndex();
 
   return sortedIndex;
 });

array/sortedLastIndex.js

@@ -1,4 +1,4 @@
-define(['../internal/baseCallback', '../internal/binaryIndex', '../internal/binaryIndexBy'], function(baseCallback, binaryIndex, binaryIndexBy) {
+define(['../internal/createSortedIndex'], function(createSortedIndex) {
 
   /**
    * This method is like `_.sortedIndex` except that it returns the highest
@@ -20,11 +20,7 @@ define(['../internal/baseCallback', '../internal/binaryIndex', '../internal/bina
    * _.sortedLastIndex([4, 4, 5, 5], 5);
    * // => 4
    */
-  function sortedLastIndex(array, value, iteratee, thisArg) {
-    return iteratee == null
-      ? binaryIndex(array, value, true)
-      : binaryIndexBy(array, value, baseCallback(iteratee, thisArg, 1), true);
-  }
+  var sortedLastIndex = createSortedIndex(true);
 
   return sortedLastIndex;
 });

array/takeRightWhile.js

@@ -1,9 +1,9 @@
-define(['../internal/baseCallback', '../internal/baseSlice'], function(baseCallback, baseSlice) {
+define(['../internal/baseCallback', '../internal/baseWhile'], function(baseCallback, baseWhile) {
 
   /**
    * Creates a slice of `array` with elements taken from the end. Elements are
    * taken until `predicate` returns falsey. The predicate is bound to `thisArg`
-   * and invoked with three arguments; (value, index, array).
+   * and invoked with three arguments: (value, index, array).
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.
@@ -50,13 +50,9 @@ define(['../internal/baseCallback', '../internal/baseSlice'], function(baseCallb
    * // => []
    */
   function takeRightWhile(array, predicate, thisArg) {
-    var length = array ? array.length : 0;
-    if (!length) {
-      return [];
-    }
-    predicate = baseCallback(predicate, thisArg, 3);
-    while (length-- && predicate(array[length], length, array)) {}
-    return baseSlice(array, length + 1);
+    return (array && array.length)
+      ? baseWhile(array, baseCallback(predicate, thisArg, 3), false, true)
+      : [];
   }
 
   return takeRightWhile;

array/takeWhile.js

@@ -1,9 +1,9 @@
-define(['../internal/baseCallback', '../internal/baseSlice'], function(baseCallback, baseSlice) {
+define(['../internal/baseCallback', '../internal/baseWhile'], function(baseCallback, baseWhile) {
 
   /**
    * Creates a slice of `array` with elements taken from the beginning. Elements
    * are taken until `predicate` returns falsey. The predicate is bound to
-   * `thisArg` and invoked with three arguments; (value, index, array).
+   * `thisArg` and invoked with three arguments: (value, index, array).
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.
@@ -50,14 +50,9 @@ define(['../internal/baseCallback', '../internal/baseSlice'], function(baseCallb
    * // => []
    */
   function takeWhile(array, predicate, thisArg) {
-    var length = array ? array.length : 0;
-    if (!length) {
-      return [];
-    }
-    var index = -1;
-    predicate = baseCallback(predicate, thisArg, 3);
-    while (++index < length && predicate(array[index], index, array)) {}
-    return baseSlice(array, 0, index);
+    return (array && array.length)
+      ? baseWhile(array, baseCallback(predicate, thisArg, 3))
+      : [];
   }
 
   return takeWhile;

array/union.js

@@ -1,13 +1,9 @@
-define(['../internal/baseFlatten', '../internal/baseUniq'], function(baseFlatten, baseUniq) {
+define(['../internal/baseFlatten', '../internal/baseUniq', '../function/restParam'], function(baseFlatten, baseUniq, restParam) {
 
   /**
    * Creates an array of unique values, in order, of the provided arrays using
-   * `SameValueZero` for equality comparisons.
-   *
-   * **Note:** `SameValueZero` comparisons are like strict equality comparisons,
-   * e.g. `===`, except that `NaN` matches `NaN`. See the
-   * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
-   * for more details.
+   * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+   * for equality comparisons.
    *
    * @static
    * @memberOf _
@@ -19,9 +15,9 @@ define(['../internal/baseFlatten', '../internal/baseUniq'], function(baseFlatten
    * _.union([1, 2], [4, 2], [2, 1]);
    * // => [1, 2, 4]
    */
-  function union() {
-    return baseUniq(baseFlatten(arguments, false, true, 0));
-  }
+  var union = restParam(function(arrays) {
+    return baseUniq(baseFlatten(arrays, false, true));
+  });
 
   return union;
 });

array/uniq.js

@@ -1,29 +1,26 @@
 define(['../internal/baseCallback', '../internal/baseUniq', '../internal/isIterateeCall', '../internal/sortedUniq'], function(baseCallback, baseUniq, isIterateeCall, sortedUniq) {
 
   /**
-   * Creates a duplicate-value-free version of an array using `SameValueZero`
-   * for equality comparisons. Providing `true` for `isSorted` performs a faster
-   * search algorithm for sorted arrays. If an iteratee function is provided it
-   * is invoked for each value in the array to generate the criterion by which
-   * uniqueness is computed. The `iteratee` is bound to `thisArg` and invoked
-   * with three arguments; (value, index, array).
+   * Creates a duplicate-free version of an array, using
+   * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+   * for equality comparisons, in which only the first occurence of each element
+   * is kept. Providing `true` for `isSorted` performs a faster search algorithm
+   * for sorted arrays. If an iteratee function is provided it is invoked for
+   * each element in the array to generate the criterion by which uniqueness
+   * is computed. The `iteratee` is bound to `thisArg` and invoked with three
+   * arguments: (value, index, array).
    *
-   * If a property name is provided for `predicate` the created `_.property`
+   * If a property name is provided for `iteratee` the created `_.property`
    * style callback returns the property value of the given element.
    *
    * If a value is also provided for `thisArg` the created `_.matchesProperty`
    * style callback returns `true` for elements that have a matching property
    * value, else `false`.
    *
-   * If an object is provided for `predicate` the created `_.matches` style
+   * If an object is provided for `iteratee` the created `_.matches` style
    * callback returns `true` for elements that have the properties of the given
    * object, else `false`.
    *
-   * **Note:** `SameValueZero` comparisons are like strict equality comparisons,
-   * e.g. `===`, except that `NaN` matches `NaN`. See the
-   * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
-   * for more details.
-   *
    * @static
    * @memberOf _
    * @alias unique
@@ -35,8 +32,8 @@ define(['../internal/baseCallback', '../internal/baseUniq', '../internal/isItera
    * @returns {Array} Returns the new duplicate-value-free array.
    * @example
    *
-   * _.uniq([1, 2, 1]);
-   * // => [1, 2]
+   * _.uniq([2, 1, 2]);
+   * // => [2, 1]
    *
    * // using `isSorted`
    * _.uniq([1, 1, 2], true);

array/unzip.js

@@ -1,11 +1,11 @@
-define(['../internal/arrayMap', '../internal/arrayMax', '../internal/baseProperty'], function(arrayMap, arrayMax, baseProperty) {
+define(['../internal/arrayFilter', '../internal/arrayMap', '../internal/baseProperty', '../internal/isArrayLike'], function(arrayFilter, arrayMap, baseProperty, isArrayLike) {
 
-  /** Used to the length of n-tuples for `_.unzip`. */
-  var getLength = baseProperty('length');
+  /* Native method references for those with the same name as other `lodash` methods. */
+  var nativeMax = Math.max;
 
   /**
    * This method is like `_.zip` except that it accepts an array of grouped
-   * elements and creates an array regrouping the elements to their pre-`_.zip`
+   * elements and creates an array regrouping the elements to their pre-zip
    * configuration.
    *
    * @static
@@ -22,10 +22,19 @@ define(['../internal/arrayMap', '../internal/arrayMax', '../internal/basePropert
    * // => [['fred', 'barney'], [30, 40], [true, false]]
    */
   function unzip(array) {
+    if (!(array && array.length)) {
+      return [];
+    }
     var index = -1,
-        length = (array && array.length && arrayMax(arrayMap(array, getLength))) >>> 0,
-        result = Array(length);
+        length = 0;
 
+    array = arrayFilter(array, function(group) {
+      if (isArrayLike(group)) {
+        length = nativeMax(group.length, length);
+        return true;
+      }
+    });
+    var result = Array(length);
     while (++index < length) {
       result[index] = arrayMap(array, baseProperty(index));
     }

array/unzipWith.js

@@ -0,0 +1,42 @@
+define(['../internal/arrayMap', '../internal/arrayReduce', '../internal/bindCallback', './unzip'], function(arrayMap, arrayReduce, bindCallback, unzip) {
+
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
+
+  /**
+   * This method is like `_.unzip` except that it accepts an iteratee to specify
+   * how regrouped values should be combined. The `iteratee` is bound to `thisArg`
+   * and invoked with four arguments: (accumulator, value, index, group).
+   *
+   * @static
+   * @memberOf _
+   * @category Array
+   * @param {Array} array The array of grouped elements to process.
+   * @param {Function} [iteratee] The function to combine regrouped values.
+   * @param {*} [thisArg] The `this` binding of `iteratee`.
+   * @returns {Array} Returns the new array of regrouped elements.
+   * @example
+   *
+   * var zipped = _.zip([1, 2], [10, 20], [100, 200]);
+   * // => [[1, 10, 100], [2, 20, 200]]
+   *
+   * _.unzipWith(zipped, _.add);
+   * // => [3, 30, 300]
+   */
+  function unzipWith(array, iteratee, thisArg) {
+    var length = array ? array.length : 0;
+    if (!length) {
+      return [];
+    }
+    var result = unzip(array);
+    if (iteratee == null) {
+      return result;
+    }
+    iteratee = bindCallback(iteratee, thisArg, 4);
+    return arrayMap(result, function(group) {
+      return arrayReduce(group, iteratee, undefined, true);
+    });
+  }
+
+  return unzipWith;
+});

array/without.js

@@ -1,13 +1,9 @@
-define(['../internal/baseDifference', '../internal/baseSlice'], function(baseDifference, baseSlice) {
+define(['../internal/baseDifference', '../internal/isArrayLike', '../function/restParam'], function(baseDifference, isArrayLike, restParam) {
 
   /**
-   * Creates an array excluding all provided values using `SameValueZero` for
-   * equality comparisons.
-   *
-   * **Note:** `SameValueZero` comparisons are like strict equality comparisons,
-   * e.g. `===`, except that `NaN` matches `NaN`. See the
-   * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
-   * for more details.
+   * Creates an array excluding all provided values using
+   * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+   * for equality comparisons.
    *
    * @static
    * @memberOf _
@@ -20,9 +16,11 @@ define(['../internal/baseDifference', '../internal/baseSlice'], function(baseDif
    * _.without([1, 2, 1, 3], 1, 2);
    * // => [3]
    */
-  function without(array) {
-    return baseDifference(array, baseSlice(arguments, 1));
-  }
+  var without = restParam(function(array, values) {
+    return isArrayLike(array)
+      ? baseDifference(array, values)
+      : [];
+  });
 
   return without;
 });

array/xor.js

@@ -1,9 +1,8 @@
-define(['../internal/baseDifference', '../internal/baseUniq', '../lang/isArguments', '../lang/isArray'], function(baseDifference, baseUniq, isArguments, isArray) {
+define(['../internal/baseDifference', '../internal/baseUniq', '../internal/isArrayLike'], function(baseDifference, baseUniq, isArrayLike) {
 
   /**
-   * Creates an array that is the symmetric difference of the provided arrays.
-   * See [Wikipedia](https://en.wikipedia.org/wiki/Symmetric_difference) for
-   * more details.
+   * Creates an array that is the [symmetric difference](https://en.wikipedia.org/wiki/Symmetric_difference)
+   * of the provided arrays.
    *
    * @static
    * @memberOf _
@@ -21,7 +20,7 @@ define(['../internal/baseDifference', '../internal/baseUniq', '../lang/isArgumen
 
     while (++index < length) {
       var array = arguments[index];
-      if (isArray(array) || isArguments(array)) {
+      if (isArrayLike(array)) {
         var result = result
           ? baseDifference(result, array).concat(baseDifference(array, result))
           : array;

array/zip.js

@@ -1,4 +1,4 @@
-define(['./unzip'], function(unzip) {
+define(['../function/restParam', './unzip'], function(restParam, unzip) {
 
   /**
    * Creates an array of grouped elements, the first of which contains the first
@@ -15,15 +15,7 @@ define(['./unzip'], function(unzip) {
    * _.zip(['fred', 'barney'], [30, 40], [true, false]);
    * // => [['fred', 30, true], ['barney', 40, false]]
    */
-  function zip() {
-    var length = arguments.length,
-        array = Array(length);
-
-    while (length--) {
-      array[length] = arguments[length];
-    }
-    return unzip(array);
-  }
+  var zip = restParam(unzip);
 
   return zip;
 });

array/zipObject.js

@@ -1,9 +1,10 @@
 define(['../lang/isArray'], function(isArray) {
 
   /**
-   * Creates an object composed from arrays of property names and values. Provide
-   * either a single two dimensional array, e.g. `[[key1, value1], [key2, value2]]`
-   * or two arrays, one of property names and one of corresponding values.
+   * The inverse of `_.pairs`; this method returns an object composed from arrays
+   * of property names and values. Provide either a single two dimensional array,
+   * e.g. `[[key1, value1], [key2, value2]]` or two arrays, one of property names
+   * and one of corresponding values.
    *
    * @static
    * @memberOf _
@@ -14,6 +15,9 @@ define(['../lang/isArray'], function(isArray) {
    * @returns {Object} Returns the new object.
    * @example
    *
+   * _.zipObject([['fred', 30], ['barney', 40]]);
+   * // => { 'fred': 30, 'barney': 40 }
+   *
    * _.zipObject(['fred', 'barney'], [30, 40]);
    * // => { 'fred': 30, 'barney': 40 }
    */

array/zipWith.js

@@ -0,0 +1,39 @@
+define(['../function/restParam', './unzipWith'], function(restParam, unzipWith) {
+
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
+
+  /**
+   * This method is like `_.zip` except that it accepts an iteratee to specify
+   * how grouped values should be combined. The `iteratee` is bound to `thisArg`
+   * and invoked with four arguments: (accumulator, value, index, group).
+   *
+   * @static
+   * @memberOf _
+   * @category Array
+   * @param {...Array} [arrays] The arrays to process.
+   * @param {Function} [iteratee] The function to combine grouped values.
+   * @param {*} [thisArg] The `this` binding of `iteratee`.
+   * @returns {Array} Returns the new array of grouped elements.
+   * @example
+   *
+   * _.zipWith([1, 2], [10, 20], [100, 200], _.add);
+   * // => [111, 222]
+   */
+  var zipWith = restParam(function(arrays) {
+    var length = arrays.length,
+        iteratee = arrays[length - 2],
+        thisArg = arrays[length - 1];
+
+    if (length > 2 && typeof iteratee == 'function') {
+      length -= 2;
+    } else {
+      iteratee = (length > 1 && typeof thisArg == 'function') ? (--length, thisArg) : undefined;
+      thisArg = undefined;
+    }
+    arrays.length = length;
+    return unzipWith(arrays, iteratee, thisArg);
+  });
+
+  return zipWith;
+});

chain/lodash.js

@@ -22,9 +22,14 @@ define(['../internal/LazyWrapper', '../internal/LodashWrapper', '../internal/bas
    * Chaining is supported in custom builds as long as the `_#value` method is
    * directly or indirectly included in the build.
    *
-   * In addition to lodash methods, wrappers also have the following `Array` methods:
-   * `concat`, `join`, `pop`, `push`, `reverse`, `shift`, `slice`, `sort`, `splice`,
-   * and `unshift`
+   * In addition to lodash methods, wrappers have `Array` and `String` methods.
+   *
+   * The wrapper `Array` methods are:
+   * `concat`, `join`, `pop`, `push`, `reverse`, `shift`, `slice`, `sort`,
+   * `splice`, and `unshift`
+   *
+   * The wrapper `String` methods are:
+   * `replace` and `split`
    *
    * The wrapper methods that support shortcut fusion are:
    * `compact`, `drop`, `dropRight`, `dropRightWhile`, `dropWhile`, `filter`,
@@ -40,8 +45,8 @@ define(['../internal/LazyWrapper', '../internal/LodashWrapper', '../internal/bas
    * `filter`, `flatten`, `flattenDeep`, `flow`, `flowRight`, `forEach`,
    * `forEachRight`, `forIn`, `forInRight`, `forOwn`, `forOwnRight`, `functions`,
    * `groupBy`, `indexBy`, `initial`, `intersection`, `invert`, `invoke`, `keys`,
-   * `keysIn`, `map`, `mapValues`, `matches`, `matchesProperty`, `memoize`, `merge`,
-   * `mixin`, `negate`, `noop`, `omit`, `once`, `pairs`, `partial`, `partialRight`,
+   * `keysIn`, `map`, `mapValues`, `matches`, `matchesProperty`, `memoize`,
+   * `merge`, `mixin`, `negate`, `omit`, `once`, `pairs`, `partial`, `partialRight`,
    * `partition`, `pick`, `plant`, `pluck`, `property`, `propertyOf`, `pull`,
    * `pullAt`, `push`, `range`, `rearg`, `reject`, `remove`, `rest`, `reverse`,
    * `shuffle`, `slice`, `sort`, `sortBy`, `sortByAll`, `sortByOrder`, `splice`,
@@ -55,15 +60,15 @@ define(['../internal/LazyWrapper', '../internal/LodashWrapper', '../internal/bas
    * `endsWith`, `escape`, `escapeRegExp`, `every`, `find`, `findIndex`, `findKey`,
    * `findLast`, `findLastIndex`, `findLastKey`, `findWhere`, `first`, `has`,
    * `identity`, `includes`, `indexOf`, `inRange`, `isArguments`, `isArray`,
-   * `isBoolean`, `isDate`, `isElement`, `isEmpty`, `isEqual`, `isError`,
-   * `isFinite`,`isFunction`, `isMatch`, `isNative`, `isNaN`, `isNull`, `isNumber`,
-   * `isObject`, `isPlainObject`, `isRegExp`, `isString`, `isUndefined`,
-   * `isTypedArray`, `join`, `kebabCase`, `last`, `lastIndexOf`, `max`, `min`,
-   * `noConflict`, `now`, `pad`, `padLeft`, `padRight`, `parseInt`, `pop`,
-   * `random`, `reduce`, `reduceRight`, `repeat`, `result`, `runInContext`,
-   * `shift`, `size`, `snakeCase`, `some`, `sortedIndex`, `sortedLastIndex`,
-   * `startCase`, `startsWith`, `sum`, `template`, `trim`, `trimLeft`,
-   * `trimRight`, `trunc`, `unescape`, `uniqueId`, `value`, and `words`
+   * `isBoolean`, `isDate`, `isElement`, `isEmpty`, `isEqual`, `isError`, `isFinite`
+   * `isFunction`, `isMatch`, `isNative`, `isNaN`, `isNull`, `isNumber`, `isObject`,
+   * `isPlainObject`, `isRegExp`, `isString`, `isUndefined`, `isTypedArray`,
+   * `join`, `kebabCase`, `last`, `lastIndexOf`, `max`, `min`, `noConflict`,
+   * `noop`, `now`, `pad`, `padLeft`, `padRight`, `parseInt`, `pop`, `random`,
+   * `reduce`, `reduceRight`, `repeat`, `result`, `runInContext`, `shift`, `size`,
+   * `snakeCase`, `some`, `sortedIndex`, `sortedLastIndex`, `startCase`, `startsWith`,
+   * `sum`, `template`, `trim`, `trimLeft`, `trimRight`, `trunc`, `unescape`,
+   * `uniqueId`, `value`, and `words`
    *
    * The wrapper method `sample` will return a wrapped value when `n` is provided,
    * otherwise an unwrapped value is returned.
@@ -78,8 +83,8 @@ define(['../internal/LazyWrapper', '../internal/LodashWrapper', '../internal/bas
    * var wrapped = _([1, 2, 3]);
    *
    * // returns an unwrapped value
-   * wrapped.reduce(function(sum, n) {
-   *   return sum + n;
+   * wrapped.reduce(function(total, n) {
+   *   return total + n;
    * });
    * // => 6
    *

chain/thru.js

@@ -12,13 +12,14 @@ define([], function() {
    * @returns {*} Returns the result of `interceptor`.
    * @example
    *
-   * _([1, 2, 3])
-   *  .last()
+   * _('  abc  ')
+   *  .chain()
+   *  .trim()
    *  .thru(function(value) {
    *    return [value];
    *  })
    *  .value();
-   * // => [3]
+   * // => ['abc']
    */
   function thru(value, interceptor, thisArg) {
     return interceptor.call(thisArg, value);

collection/at.js

@@ -1,4 +1,4 @@
-define(['../internal/baseAt', '../internal/baseFlatten', '../internal/isLength', '../internal/toIterable'], function(baseAt, baseFlatten, isLength, toIterable) {
+define(['../internal/baseAt', '../internal/baseFlatten', '../function/restParam'], function(baseAt, baseFlatten, restParam) {
 
   /**
    * Creates an array of elements corresponding to the given keys, or indexes,
@@ -17,16 +17,12 @@ define(['../internal/baseAt', '../internal/baseFlatten', '../internal/isLength',
    * _.at(['a', 'b', 'c'], [0, 2]);
    * // => ['a', 'c']
    *
-   * _.at(['fred', 'barney', 'pebbles'], 0, 2);
-   * // => ['fred', 'pebbles']
+   * _.at(['barney', 'fred', 'pebbles'], 0, 2);
+   * // => ['barney', 'pebbles']
    */
-  function at(collection) {
-    var length = collection ? collection.length : 0;
-    if (isLength(length)) {
-      collection = toIterable(collection);
-    }
-    return baseAt(collection, baseFlatten(arguments, false, false, 1));
-  }
+  var at = restParam(function(collection, props) {
+    return baseAt(collection, baseFlatten(props));
+  });
 
   return at;
 });

collection/countBy.js

@@ -10,17 +10,17 @@ define(['../internal/createAggregator'], function(createAggregator) {
    * Creates an object composed of keys generated from the results of running
    * each element of `collection` through `iteratee`. The corresponding value
    * of each key is the number of times the key was returned by `iteratee`.
-   * The `iteratee` is bound to `thisArg` and invoked with three arguments;
+   * The `iteratee` is bound to `thisArg` and invoked with three arguments:
    * (value, index|key, collection).
    *
-   * If a property name is provided for `predicate` the created `_.property`
+   * If a property name is provided for `iteratee` the created `_.property`
    * style callback returns the property value of the given element.
    *
    * If a value is also provided for `thisArg` the created `_.matchesProperty`
    * style callback returns `true` for elements that have a matching property
    * value, else `false`.
    *
-   * If an object is provided for `predicate` the created `_.matches` style
+   * If an object is provided for `iteratee` the created `_.matches` style
    * callback returns `true` for elements that have the properties of the given
    * object, else `false`.
    *

collection/every.js

@@ -1,8 +1,11 @@
-define(['../internal/arrayEvery', '../internal/baseCallback', '../internal/baseEvery', '../lang/isArray'], function(arrayEvery, baseCallback, baseEvery, isArray) {
+define(['../internal/arrayEvery', '../internal/baseCallback', '../internal/baseEvery', '../lang/isArray', '../internal/isIterateeCall'], function(arrayEvery, baseCallback, baseEvery, isArray, isIterateeCall) {
+
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
 
   /**
    * Checks if `predicate` returns truthy for **all** elements of `collection`.
-   * The predicate is bound to `thisArg` and invoked with three arguments;
+   * The predicate is bound to `thisArg` and invoked with three arguments:
    * (value, index|key, collection).
    *
    * If a property name is provided for `predicate` the created `_.property`
@@ -50,7 +53,10 @@ define(['../internal/arrayEvery', '../internal/baseCallback', '../internal/baseE
    */
   function every(collection, predicate, thisArg) {
     var func = isArray(collection) ? arrayEvery : baseEvery;
-    if (typeof predicate != 'function' || typeof thisArg != 'undefined') {
+    if (thisArg && isIterateeCall(collection, predicate, thisArg)) {
+      predicate = null;
+    }
+    if (typeof predicate != 'function' || thisArg !== undefined) {
       predicate = baseCallback(predicate, thisArg, 3);
     }
     return func(collection, predicate);

collection/filter.js

@@ -3,7 +3,7 @@ define(['../internal/arrayFilter', '../internal/baseCallback', '../internal/base
   /**
    * Iterates over elements of `collection`, returning an array of all elements
    * `predicate` returns truthy for. The predicate is bound to `thisArg` and
-   * invoked with three arguments; (value, index|key, collection).
+   * invoked with three arguments: (value, index|key, collection).
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.

collection/find.js

@@ -1,12 +1,9 @@
-define(['../internal/baseCallback', '../internal/baseEach', '../internal/baseFind', '../array/findIndex', '../lang/isArray'], function(baseCallback, baseEach, baseFind, findIndex, isArray) {
-
-  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
-  var undefined;
+define(['../internal/baseEach', '../internal/createFind'], function(baseEach, createFind) {
 
   /**
    * Iterates over elements of `collection`, returning the first element
    * `predicate` returns truthy for. The predicate is bound to `thisArg` and
-   * invoked with three arguments; (value, index|key, collection).
+   * invoked with three arguments: (value, index|key, collection).
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.
@@ -53,14 +50,7 @@ define(['../internal/baseCallback', '../internal/baseEach', '../internal/baseFin
    * _.result(_.find(users, 'active'), 'user');
    * // => 'barney'
    */
-  function find(collection, predicate, thisArg) {
-    if (isArray(collection)) {
-      var index = findIndex(collection, predicate, thisArg);
-      return index > -1 ? collection[index] : undefined;
-    }
-    predicate = baseCallback(predicate, thisArg, 3);
-    return baseFind(collection, predicate, baseEach);
-  }
+  var find = createFind(baseEach);
 
   return find;
 });

collection/findLast.js

@@ -1,4 +1,4 @@
-define(['../internal/baseCallback', '../internal/baseEachRight', '../internal/baseFind'], function(baseCallback, baseEachRight, baseFind) {
+define(['../internal/baseEachRight', '../internal/createFind'], function(baseEachRight, createFind) {
 
   /**
    * This method is like `_.find` except that it iterates over elements of
@@ -19,10 +19,7 @@ define(['../internal/baseCallback', '../internal/baseEachRight', '../internal/ba
    * });
    * // => 3
    */
-  function findLast(collection, predicate, thisArg) {
-    predicate = baseCallback(predicate, thisArg, 3);
-    return baseFind(collection, predicate, baseEachRight);
-  }
+  var findLast = createFind(baseEachRight, true);
 
   return findLast;
 });

collection/forEach.js

@@ -1,12 +1,12 @@
-define(['../internal/arrayEach', '../internal/baseEach', '../internal/bindCallback', '../lang/isArray'], function(arrayEach, baseEach, bindCallback, isArray) {
+define(['../internal/arrayEach', '../internal/baseEach', '../internal/createForEach'], function(arrayEach, baseEach, createForEach) {
 
   /**
    * Iterates over elements of `collection` invoking `iteratee` for each element.
-   * The `iteratee` is bound to `thisArg` and invoked with three arguments;
-   * (value, index|key, collection). Iterator functions may exit iteration early
+   * The `iteratee` is bound to `thisArg` and invoked with three arguments:
+   * (value, index|key, collection). Iteratee functions may exit iteration early
    * by explicitly returning `false`.
    *
-   * **Note:** As with other "Collections" methods, objects with a `length` property
+   * **Note:** As with other "Collections" methods, objects with a "length" property
    * are iterated like arrays. To avoid this behavior `_.forIn` or `_.forOwn`
    * may be used for object iteration.
    *
@@ -30,11 +30,7 @@ define(['../internal/arrayEach', '../internal/baseEach', '../internal/bindCallba
    * });
    * // => logs each value-key pair and returns the object (iteration order is not guaranteed)
    */
-  function forEach(collection, iteratee, thisArg) {
-    return (typeof iteratee == 'function' && typeof thisArg == 'undefined' && isArray(collection))
-      ? arrayEach(collection, iteratee)
-      : baseEach(collection, bindCallback(iteratee, thisArg, 3));
-  }
+  var forEach = createForEach(arrayEach, baseEach);
 
   return forEach;
 });

collection/forEachRight.js

@@ -1,4 +1,4 @@
-define(['../internal/arrayEachRight', '../internal/baseEachRight', '../internal/bindCallback', '../lang/isArray'], function(arrayEachRight, baseEachRight, bindCallback, isArray) {
+define(['../internal/arrayEachRight', '../internal/baseEachRight', '../internal/createForEach'], function(arrayEachRight, baseEachRight, createForEach) {
 
   /**
    * This method is like `_.forEach` except that it iterates over elements of
@@ -16,14 +16,10 @@ define(['../internal/arrayEachRight', '../internal/baseEachRight', '../internal/
    *
    * _([1, 2]).forEachRight(function(n) {
    *   console.log(n);
-   * }).join(',');
+   * }).value();
    * // => logs each value from right to left and returns the array
    */
-  function forEachRight(collection, iteratee, thisArg) {
-    return (typeof iteratee == 'function' && typeof thisArg == 'undefined' && isArray(collection))
-      ? arrayEachRight(collection, iteratee)
-      : baseEachRight(collection, bindCallback(iteratee, thisArg, 3));
-  }
+  var forEachRight = createForEach(arrayEachRight, baseEachRight);
 
   return forEachRight;
 });

collection/groupBy.js

@@ -10,17 +10,17 @@ define(['../internal/createAggregator'], function(createAggregator) {
    * Creates an object composed of keys generated from the results of running
    * each element of `collection` through `iteratee`. The corresponding value
    * of each key is an array of the elements responsible for generating the key.
-   * The `iteratee` is bound to `thisArg` and invoked with three arguments;
+   * The `iteratee` is bound to `thisArg` and invoked with three arguments:
    * (value, index|key, collection).
    *
-   * If a property name is provided for `predicate` the created `_.property`
+   * If a property name is provided for `iteratee` the created `_.property`
    * style callback returns the property value of the given element.
    *
    * If a value is also provided for `thisArg` the created `_.matchesProperty`
    * style callback returns `true` for elements that have a matching property
    * value, else `false`.
    *
-   * If an object is provided for `predicate` the created `_.matches` style
+   * If an object is provided for `iteratee` the created `_.matches` style
    * callback returns `true` for elements that have the properties of the given
    * object, else `false`.
    *

collection/includes.js

@@ -1,17 +1,13 @@
-define(['../internal/baseIndexOf', '../lang/isArray', '../internal/isLength', '../lang/isString', '../object/values'], function(baseIndexOf, isArray, isLength, isString, values) {
+define(['../internal/baseIndexOf', '../internal/getLength', '../lang/isArray', '../internal/isIterateeCall', '../internal/isLength', '../lang/isString', '../object/values'], function(baseIndexOf, getLength, isArray, isIterateeCall, isLength, isString, values) {
 
   /* Native method references for those with the same name as other `lodash` methods. */
   var nativeMax = Math.max;
 
   /**
-   * Checks if `value` is in `collection` using `SameValueZero` for equality
-   * comparisons. If `fromIndex` is negative, it is used as the offset from
-   * the end of `collection`.
-   *
-   * **Note:** `SameValueZero` comparisons are like strict equality comparisons,
-   * e.g. `===`, except that `NaN` matches `NaN`. See the
-   * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
-   * for more details.
+   * Checks if `value` is in `collection` using
+   * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+   * for equality comparisons. If `fromIndex` is negative, it is used as the offset
+   * from the end of `collection`.
    *
    * @static
    * @memberOf _
@@ -20,6 +16,7 @@ define(['../internal/baseIndexOf', '../lang/isArray', '../internal/isLength', '.
    * @param {Array|Object|string} collection The collection to search.
    * @param {*} target The value to search for.
    * @param {number} [fromIndex=0] The index to search from.
+   * @param- {Object} [guard] Enables use as a callback for functions like `_.reduce`.
    * @returns {boolean} Returns `true` if a matching element is found, else `false`.
    * @example
    *
@@ -35,8 +32,8 @@ define(['../internal/baseIndexOf', '../lang/isArray', '../internal/isLength', '.
    * _.includes('pebbles', 'eb');
    * // => true
    */
-  function includes(collection, target, fromIndex) {
-    var length = collection ? collection.length : 0;
+  function includes(collection, target, fromIndex, guard) {
+    var length = collection ? getLength(collection) : 0;
     if (!isLength(length)) {
       collection = values(collection);
       length = collection.length;
@@ -44,10 +41,10 @@ define(['../internal/baseIndexOf', '../lang/isArray', '../internal/isLength', '.
     if (!length) {
       return false;
     }
-    if (typeof fromIndex == 'number') {
-      fromIndex = fromIndex < 0 ? nativeMax(length + fromIndex, 0) : (fromIndex || 0);
-    } else {
+    if (typeof fromIndex != 'number' || (guard && isIterateeCall(target, fromIndex, guard))) {
       fromIndex = 0;
+    } else {
+      fromIndex = fromIndex < 0 ? nativeMax(length + fromIndex, 0) : (fromIndex || 0);
     }
     return (typeof collection == 'string' || !isArray(collection) && isString(collection))
       ? (fromIndex < length && collection.indexOf(target, fromIndex) > -1)

collection/indexBy.js

@@ -4,17 +4,17 @@ define(['../internal/createAggregator'], function(createAggregator) {
    * Creates an object composed of keys generated from the results of running
    * each element of `collection` through `iteratee`. The corresponding value
    * of each key is the last element responsible for generating the key. The
-   * iteratee function is bound to `thisArg` and invoked with three arguments;
+   * iteratee function is bound to `thisArg` and invoked with three arguments:
    * (value, index|key, collection).
    *
-   * If a property name is provided for `predicate` the created `_.property`
+   * If a property name is provided for `iteratee` the created `_.property`
    * style callback returns the property value of the given element.
    *
    * If a value is also provided for `thisArg` the created `_.matchesProperty`
    * style callback returns `true` for elements that have a matching property
    * value, else `false`.
    *
-   * If an object is provided for `predicate` the created `_.matches` style
+   * If an object is provided for `iteratee` the created `_.matches` style
    * callback returns `true` for elements that have the properties of the given
    * object, else `false`.
    *

collection/invoke.js

@@ -1,16 +1,16 @@
-define(['../internal/baseInvoke', '../internal/baseSlice'], function(baseInvoke, baseSlice) {
+define(['../internal/baseEach', '../internal/invokePath', '../internal/isArrayLike', '../internal/isKey', '../function/restParam'], function(baseEach, invokePath, isArrayLike, isKey, restParam) {
 
   /**
-   * Invokes the method named by `methodName` on each element in `collection`,
-   * returning an array of the results of each invoked method. Any additional
-   * arguments are provided to each invoked method. If `methodName` is a function
-   * it is invoked for, and `this` bound to, each element in `collection`.
+   * Invokes the method at `path` on each element in `collection`, returning
+   * an array of the results of each invoked method. Any additional arguments
+   * are provided to each invoked method. If `methodName` is a function it is
+   * invoked for, and `this` bound to, each element in `collection`.
    *
    * @static
    * @memberOf _
    * @category Collection
    * @param {Array|Object|string} collection The collection to iterate over.
-   * @param {Function|string} methodName The name of the method to invoke or
+   * @param {Array|Function|string} path The path of the method to invoke or
    *  the function invoked per iteration.
    * @param {...*} [args] The arguments to invoke the method with.
    * @returns {Array} Returns the array of results.
@@ -22,9 +22,18 @@ define(['../internal/baseInvoke', '../internal/baseSlice'], function(baseInvoke,
    * _.invoke([123, 456], String.prototype.split, '');
    * // => [['1', '2', '3'], ['4', '5', '6']]
    */
-  function invoke(collection, methodName) {
-    return baseInvoke(collection, methodName, baseSlice(arguments, 2));
-  }
+  var invoke = restParam(function(collection, path, args) {
+    var index = -1,
+        isFunc = typeof path == 'function',
+        isProp = isKey(path),
+        result = isArrayLike(collection) ? Array(collection.length) : [];
+
+    baseEach(collection, function(value) {
+      var func = isFunc ? path : (isProp && value != null && value[path]);
+      result[++index] = func ? func.apply(value, args) : invokePath(value, path, args);
+    });
+    return result;
+  });
 
   return invoke;
 });

collection/map.js

@@ -3,16 +3,16 @@ define(['../internal/arrayMap', '../internal/baseCallback', '../internal/baseMap
   /**
    * Creates an array of values by running each element in `collection` through
    * `iteratee`. The `iteratee` is bound to `thisArg` and invoked with three
-   * arguments; (value, index|key, collection).
+   * arguments: (value, index|key, collection).
    *
-   * If a property name is provided for `predicate` the created `_.property`
+   * If a property name is provided for `iteratee` the created `_.property`
    * style callback returns the property value of the given element.
    *
    * If a value is also provided for `thisArg` the created `_.matchesProperty`
    * style callback returns `true` for elements that have a matching property
    * value, else `false`.
    *
-   * If an object is provided for `predicate` the created `_.matches` style
+   * If an object is provided for `iteratee` the created `_.matches` style
    * callback returns `true` for elements that have the properties of the given
    * object, else `false`.
    *
@@ -20,10 +20,11 @@ define(['../internal/arrayMap', '../internal/baseCallback', '../internal/baseMap
    * `_.every`, `_.filter`, `_.map`, `_.mapValues`, `_.reject`, and `_.some`.
    *
    * The guarded methods are:
-   * `ary`, `callback`, `chunk`, `clone`, `create`, `curry`, `curryRight`, `drop`,
-   * `dropRight`, `fill`, `flatten`, `invert`, `max`, `min`, `parseInt`, `slice`,
-   * `sortBy`, `take`, `takeRight`, `template`, `trim`, `trimLeft`, `trimRight`,
-   * `trunc`, `random`, `range`, `sample`, `uniq`, and `words`
+   * `ary`, `callback`, `chunk`, `clone`, `create`, `curry`, `curryRight`,
+   * `drop`, `dropRight`, `every`, `fill`, `flatten`, `invert`, `max`, `min`,
+   * `parseInt`, `slice`, `sortBy`, `take`, `takeRight`, `template`, `trim`,
+   * `trimLeft`, `trimRight`, `trunc`, `random`, `range`, `sample`, `some`,
+   * `sum`, `uniq`, and `words`
    *
    * @static
    * @memberOf _
@@ -32,7 +33,6 @@ define(['../internal/arrayMap', '../internal/baseCallback', '../internal/baseMap
    * @param {Array|Object|string} collection The collection to iterate over.
    * @param {Function|Object|string} [iteratee=_.identity] The function invoked
    *  per iteration.
-   *  create a `_.property` or `_.matches` style callback respectively.
    * @param {*} [thisArg] The `this` binding of `iteratee`.
    * @returns {Array} Returns the new mapped array.
    * @example

collection/partition.js

@@ -4,7 +4,7 @@ define(['../internal/createAggregator'], function(createAggregator) {
    * Creates an array of elements split into two groups, the first of which
    * contains elements `predicate` returns truthy for, while the second of which
    * contains elements `predicate` returns falsey for. The predicate is bound
-   * to `thisArg` and invoked with three arguments; (value, index|key, collection).
+   * to `thisArg` and invoked with three arguments: (value, index|key, collection).
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.

collection/pluck.js

@@ -1,13 +1,13 @@
-define(['../internal/baseProperty', './map'], function(baseProperty, map) {
+define(['./map', '../utility/property'], function(map, property) {
 
   /**
-   * Gets the value of `key` from all elements in `collection`.
+   * Gets the property value of `path` from all elements in `collection`.
    *
    * @static
    * @memberOf _
    * @category Collection
    * @param {Array|Object|string} collection The collection to iterate over.
-   * @param {string} key The key of the property to pluck.
+   * @param {Array|string} path The path of the property to pluck.
    * @returns {Array} Returns the property values.
    * @example
    *
@@ -23,8 +23,8 @@ define(['../internal/baseProperty', './map'], function(baseProperty, map) {
    * _.pluck(userIndex, 'age');
    * // => [36, 40] (iteration order is not guaranteed)
    */
-  function pluck(collection, key) {
-    return map(collection, baseProperty(key));
+  function pluck(collection, path) {
+    return map(collection, property(path));
   }
 
   return pluck;

collection/reduce.js

@@ -1,18 +1,18 @@
-define(['../internal/arrayReduce', '../internal/baseCallback', '../internal/baseEach', '../internal/baseReduce', '../lang/isArray'], function(arrayReduce, baseCallback, baseEach, baseReduce, isArray) {
+define(['../internal/arrayReduce', '../internal/baseEach', '../internal/createReduce'], function(arrayReduce, baseEach, createReduce) {
 
   /**
    * Reduces `collection` to a value which is the accumulated result of running
    * each element in `collection` through `iteratee`, where each successive
    * invocation is supplied the return value of the previous. If `accumulator`
    * is not provided the first element of `collection` is used as the initial
-   * value. The `iteratee` is bound to `thisArg`and invoked with four arguments;
+   * value. The `iteratee` is bound to `thisArg` and invoked with four arguments:
    * (accumulator, value, index|key, collection).
    *
    * Many lodash methods are guarded to work as interatees for methods like
    * `_.reduce`, `_.reduceRight`, and `_.transform`.
    *
    * The guarded methods are:
-   * `assign`, `defaults`, `merge`, and `sortAllBy`
+   * `assign`, `defaults`, `includes`, `merge`, `sortByAll`, and `sortByOrder`
    *
    * @static
    * @memberOf _
@@ -25,8 +25,8 @@ define(['../internal/arrayReduce', '../internal/baseCallback', '../internal/base
    * @returns {*} Returns the accumulated value.
    * @example
    *
-   * _.reduce([1, 2], function(sum, n) {
-   *   return sum + n;
+   * _.reduce([1, 2], function(total, n) {
+   *   return total + n;
    * });
    * // => 3
    *
@@ -36,10 +36,7 @@ define(['../internal/arrayReduce', '../internal/baseCallback', '../internal/base
    * }, {});
    * // => { 'a': 3, 'b': 6 } (iteration order is not guaranteed)
    */
-  function reduce(collection, iteratee, accumulator, thisArg) {
-    var func = isArray(collection) ? arrayReduce : baseReduce;
-    return func(collection, baseCallback(iteratee, thisArg, 4), accumulator, arguments.length < 3, baseEach);
-  }
+  var reduce = createReduce(arrayReduce, baseEach);
 
   return reduce;
 });

collection/reduceRight.js

@@ -1,4 +1,4 @@
-define(['../internal/arrayReduceRight', '../internal/baseCallback', '../internal/baseEachRight', '../internal/baseReduce', '../lang/isArray'], function(arrayReduceRight, baseCallback, baseEachRight, baseReduce, isArray) {
+define(['../internal/arrayReduceRight', '../internal/baseEachRight', '../internal/createReduce'], function(arrayReduceRight, baseEachRight, createReduce) {
 
   /**
    * This method is like `_.reduce` except that it iterates over elements of
@@ -22,10 +22,7 @@ define(['../internal/arrayReduceRight', '../internal/baseCallback', '../internal
    * }, []);
    * // => [4, 5, 2, 3, 0, 1]
    */
-  function reduceRight(collection, iteratee, accumulator, thisArg) {
-    var func = isArray(collection) ? arrayReduceRight : baseReduce;
-    return func(collection, baseCallback(iteratee, thisArg, 4), accumulator, arguments.length < 3, baseEachRight);
-  }
+  var reduceRight = createReduce(arrayReduceRight, baseEachRight);
 
   return reduceRight;
 });

collection/reject.js

@@ -4,17 +4,6 @@ define(['../internal/arrayFilter', '../internal/baseCallback', '../internal/base
    * The opposite of `_.filter`; this method returns the elements of `collection`
    * that `predicate` does **not** return truthy for.
    *
-   * If a property name is provided for `predicate` the created `_.property`
-   * style callback returns the property value of the given element.
-   *
-   * If a value is also provided for `thisArg` the created `_.matchesProperty`
-   * style callback returns `true` for elements that have a matching property
-   * value, else `false`.
-   *
-   * If an object is provided for `predicate` the created `_.matches` style
-   * callback returns `true` for elements that have the properties of the given
-   * object, else `false`.
-   *
    * @static
    * @memberOf _
    * @category Collection

collection/shuffle.js

@@ -1,9 +1,8 @@
 define(['../internal/baseRandom', '../internal/toIterable'], function(baseRandom, toIterable) {
 
   /**
-   * Creates an array of shuffled values, using a version of the Fisher-Yates
-   * shuffle. See [Wikipedia](https://en.wikipedia.org/wiki/Fisher-Yates_shuffle)
-   * for more details.
+   * Creates an array of shuffled values, using a version of the
+   * [Fisher-Yates shuffle](https://en.wikipedia.org/wiki/Fisher-Yates_shuffle).
    *
    * @static
    * @memberOf _

collection/size.js

@@ -1,4 +1,4 @@
-define(['../internal/isLength', '../object/keys'], function(isLength, keys) {
+define(['../internal/getLength', '../internal/isLength', '../object/keys'], function(getLength, isLength, keys) {
 
   /**
    * Gets the size of `collection` by returning its length for array-like
@@ -21,7 +21,7 @@ define(['../internal/isLength', '../object/keys'], function(isLength, keys) {
    * // => 7
    */
   function size(collection) {
-    var length = collection ? collection.length : 0;
+    var length = collection ? getLength(collection) : 0;
     return isLength(length) ? length : keys(collection).length;
   }
 

collection/some.js

@@ -1,10 +1,13 @@
-define(['../internal/arraySome', '../internal/baseCallback', '../internal/baseSome', '../lang/isArray'], function(arraySome, baseCallback, baseSome, isArray) {
+define(['../internal/arraySome', '../internal/baseCallback', '../internal/baseSome', '../lang/isArray', '../internal/isIterateeCall'], function(arraySome, baseCallback, baseSome, isArray, isIterateeCall) {
+
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
 
   /**
    * Checks if `predicate` returns truthy for **any** element of `collection`.
    * The function returns as soon as it finds a passing value and does not iterate
    * over the entire collection. The predicate is bound to `thisArg` and invoked
-   * with three arguments; (value, index|key, collection).
+   * with three arguments: (value, index|key, collection).
    *
    * If a property name is provided for `predicate` the created `_.property`
    * style callback returns the property value of the given element.
@@ -51,7 +54,10 @@ define(['../internal/arraySome', '../internal/baseCallback', '../internal/baseSo
    */
   function some(collection, predicate, thisArg) {
     var func = isArray(collection) ? arraySome : baseSome;
-    if (typeof predicate != 'function' || typeof thisArg != 'undefined') {
+    if (thisArg && isIterateeCall(collection, predicate, thisArg)) {
+      predicate = null;
+    }
+    if (typeof predicate != 'function' || thisArg !== undefined) {
       predicate = baseCallback(predicate, thisArg, 3);
     }
     return func(collection, predicate);

collection/sortBy.js

@@ -1,20 +1,20 @@
-define(['../internal/baseCallback', '../internal/baseEach', '../internal/baseSortBy', '../internal/compareAscending', '../internal/isIterateeCall', '../internal/isLength'], function(baseCallback, baseEach, baseSortBy, compareAscending, isIterateeCall, isLength) {
+define(['../internal/baseCallback', '../internal/baseMap', '../internal/baseSortBy', '../internal/compareAscending', '../internal/isIterateeCall'], function(baseCallback, baseMap, baseSortBy, compareAscending, isIterateeCall) {
 
   /**
    * Creates an array of elements, sorted in ascending order by the results of
    * running each element in a collection through `iteratee`. This method performs
    * a stable sort, that is, it preserves the original sort order of equal elements.
-   * The `iteratee` is bound to `thisArg` and invoked with three arguments;
+   * The `iteratee` is bound to `thisArg` and invoked with three arguments:
    * (value, index|key, collection).
    *
-   * If a property name is provided for `predicate` the created `_.property`
+   * If a property name is provided for `iteratee` the created `_.property`
    * style callback returns the property value of the given element.
    *
    * If a value is also provided for `thisArg` the created `_.matchesProperty`
    * style callback returns `true` for elements that have a matching property
    * value, else `false`.
    *
-   * If an object is provided for `predicate` the created `_.matches` style
+   * If an object is provided for `iteratee` the created `_.matches` style
    * callback returns `true` for elements that have the properties of the given
    * object, else `false`.
    *
@@ -22,9 +22,8 @@ define(['../internal/baseCallback', '../internal/baseEach', '../internal/baseSor
    * @memberOf _
    * @category Collection
    * @param {Array|Object|string} collection The collection to iterate over.
-   * @param {Array|Function|Object|string} [iteratee=_.identity] The function
-   *  invoked per iteration. If a property name or an object is provided it is
-   *  used to create a `_.property` or `_.matches` style callback respectively.
+   * @param {Function|Object|string} [iteratee=_.identity] The function invoked
+   *  per iteration.
    * @param {*} [thisArg] The `this` binding of `iteratee`.
    * @returns {Array} Returns the new sorted array.
    * @example
@@ -53,16 +52,14 @@ define(['../internal/baseCallback', '../internal/baseEach', '../internal/baseSor
     if (collection == null) {
       return [];
     }
-    var index = -1,
-        length = collection.length,
-        result = isLength(length) ? Array(length) : [];
-
     if (thisArg && isIterateeCall(collection, iteratee, thisArg)) {
       iteratee = null;
     }
+    var index = -1;
     iteratee = baseCallback(iteratee, thisArg, 3);
-    baseEach(collection, function(value, key, collection) {
-      result[++index] = { 'criteria': iteratee(value, key, collection), 'index': index, 'value': value };
+
+    var result = baseMap(collection, function(value, key, collection) {
+      return { 'criteria': iteratee(value, key, collection), 'index': ++index, 'value': value };
     });
     return baseSortBy(result, compareAscending);
   }

collection/sortByAll.js

@@ -1,40 +1,50 @@
-define(['../internal/baseFlatten', '../internal/baseSortByOrder', '../internal/isIterateeCall'], function(baseFlatten, baseSortByOrder, isIterateeCall) {
+define(['../internal/baseFlatten', '../internal/baseSortByOrder', '../internal/isIterateeCall', '../function/restParam'], function(baseFlatten, baseSortByOrder, isIterateeCall, restParam) {
 
   /**
-   * This method is like `_.sortBy` except that it sorts by property names
-   * instead of an iteratee function.
+   * This method is like `_.sortBy` except that it can sort by multiple iteratees
+   * or property names.
+   *
+   * If a property name is provided for an iteratee the created `_.property`
+   * style callback returns the property value of the given element.
+   *
+   * If an object is provided for an iteratee the created `_.matches` style
+   * callback returns `true` for elements that have the properties of the given
+   * object, else `false`.
    *
    * @static
    * @memberOf _
    * @category Collection
    * @param {Array|Object|string} collection The collection to iterate over.
-   * @param {...(string|string[])} props The property names to sort by,
-   *  specified as individual property names or arrays of property names.
+   * @param {...(Function|Function[]|Object|Object[]|string|string[])} iteratees
+   *  The iteratees to sort by, specified as individual values or arrays of values.
    * @returns {Array} Returns the new sorted array.
    * @example
    *
    * var users = [
+   *   { 'user': 'fred',   'age': 48 },
    *   { 'user': 'barney', 'age': 36 },
-   *   { 'user': 'fred',   'age': 40 },
-   *   { 'user': 'barney', 'age': 26 },
-   *   { 'user': 'fred',   'age': 30 }
+   *   { 'user': 'fred',   'age': 42 },
+   *   { 'user': 'barney', 'age': 34 }
    * ];
    *
    * _.map(_.sortByAll(users, ['user', 'age']), _.values);
-   * // => [['barney', 26], ['barney', 36], ['fred', 30], ['fred', 40]]
+   * // => [['barney', 34], ['barney', 36], ['fred', 42], ['fred', 48]]
+   *
+   * _.map(_.sortByAll(users, 'user', function(chr) {
+   *   return Math.floor(chr.age / 10);
+   * }), _.values);
+   * // => [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 42]]
    */
-  function sortByAll(collection) {
+  var sortByAll = restParam(function(collection, iteratees) {
     if (collection == null) {
       return [];
     }
-    var args = arguments,
-        guard = args[3];
-
-    if (guard && isIterateeCall(args[1], args[2], guard)) {
-      args = [collection, args[1]];
+    var guard = iteratees[2];
+    if (guard && isIterateeCall(iteratees[0], iteratees[1], guard)) {
+      iteratees.length = 1;
     }
-    return baseSortByOrder(collection, baseFlatten(args, false, false, 1), []);
-  }
+    return baseSortByOrder(collection, baseFlatten(iteratees), []);
+  });
 
   return sortByAll;
 });

collection/sortByOrder.js

@@ -2,44 +2,52 @@ define(['../internal/baseSortByOrder', '../lang/isArray', '../internal/isIterate
 
   /**
    * This method is like `_.sortByAll` except that it allows specifying the
-   * sort orders of the property names to sort by. A truthy value in `orders`
-   * will sort the corresponding property name in ascending order while a
-   * falsey value will sort it in descending order.
+   * sort orders of the iteratees to sort by. A truthy value in `orders` will
+   * sort the corresponding property name in ascending order while a falsey
+   * value will sort it in descending order.
+   *
+   * If a property name is provided for an iteratee the created `_.property`
+   * style callback returns the property value of the given element.
+   *
+   * If an object is provided for an iteratee the created `_.matches` style
+   * callback returns `true` for elements that have the properties of the given
+   * object, else `false`.
    *
    * @static
    * @memberOf _
    * @category Collection
    * @param {Array|Object|string} collection The collection to iterate over.
-   * @param {string[]} props The property names to sort by.
-   * @param {boolean[]} orders The sort orders of `props`.
+   * @param {Function[]|Object[]|string[]} iteratees The iteratees to sort by.
+   * @param {boolean[]} orders The sort orders of `iteratees`.
+   * @param- {Object} [guard] Enables use as a callback for functions like `_.reduce`.
    * @returns {Array} Returns the new sorted array.
    * @example
    *
    * var users = [
-   *   { 'user': 'barney', 'age': 36 },
-   *   { 'user': 'fred',   'age': 40 },
-   *   { 'user': 'barney', 'age': 26 },
-   *   { 'user': 'fred',   'age': 30 }
+   *   { 'user': 'fred',   'age': 48 },
+   *   { 'user': 'barney', 'age': 34 },
+   *   { 'user': 'fred',   'age': 42 },
+   *   { 'user': 'barney', 'age': 36 }
    * ];
    *
    * // sort by `user` in ascending order and by `age` in descending order
    * _.map(_.sortByOrder(users, ['user', 'age'], [true, false]), _.values);
-   * // => [['barney', 36], ['barney', 26], ['fred', 40], ['fred', 30]]
+   * // => [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 42]]
    */
-  function sortByOrder(collection, props, orders, guard) {
+  function sortByOrder(collection, iteratees, orders, guard) {
     if (collection == null) {
       return [];
     }
-    if (guard && isIterateeCall(props, orders, guard)) {
+    if (guard && isIterateeCall(iteratees, orders, guard)) {
       orders = null;
     }
-    if (!isArray(props)) {
-      props = props == null ? [] : [props];
+    if (!isArray(iteratees)) {
+      iteratees = iteratees == null ? [] : [iteratees];
     }
     if (!isArray(orders)) {
       orders = orders == null ? [] : [orders];
     }
-    return baseSortByOrder(collection, props, orders);
+    return baseSortByOrder(collection, iteratees, orders);
   }
 
   return sortByOrder;

function.js

@@ -1,4 +1,4 @@
-define(['./function/after', './function/ary', './function/backflow', './function/before', './function/bind', './function/bindAll', './function/bindKey', './function/compose', './function/curry', './function/curryRight', './function/debounce', './function/defer', './function/delay', './function/flow', './function/flowRight', './function/memoize', './function/negate', './function/once', './function/partial', './function/partialRight', './function/rearg', './function/spread', './function/throttle', './function/wrap'], function(after, ary, backflow, before, bind, bindAll, bindKey, compose, curry, curryRight, debounce, defer, delay, flow, flowRight, memoize, negate, once, partial, partialRight, rearg, spread, throttle, wrap) {
+define(['./function/after', './function/ary', './function/backflow', './function/before', './function/bind', './function/bindAll', './function/bindKey', './function/compose', './function/curry', './function/curryRight', './function/debounce', './function/defer', './function/delay', './function/flow', './function/flowRight', './function/memoize', './function/negate', './function/once', './function/partial', './function/partialRight', './function/rearg', './function/restParam', './function/spread', './function/throttle', './function/wrap'], function(after, ary, backflow, before, bind, bindAll, bindKey, compose, curry, curryRight, debounce, defer, delay, flow, flowRight, memoize, negate, once, partial, partialRight, rearg, restParam, spread, throttle, wrap) {
   return {
     'after': after,
     'ary': ary,
@@ -21,6 +21,7 @@ define(['./function/after', './function/ary', './function/backflow', './function
     'partial': partial,
     'partialRight': partialRight,
     'rearg': rearg,
+    'restParam': restParam,
     'spread': spread,
     'throttle': throttle,
     'wrap': wrap

function/ary.js

@@ -1,7 +1,7 @@
 define(['../internal/createWrapper', '../internal/isIterateeCall'], function(createWrapper, isIterateeCall) {
 
   /** Used to compose bitmasks for wrapper metadata. */
-  var ARY_FLAG = 256;
+  var ARY_FLAG = 128;
 
   /* Native method references for those with the same name as other `lodash` methods. */
   var nativeMax = Math.max;

function/before.js

@@ -33,7 +33,8 @@ define([], function() {
     return function() {
       if (--n > 0) {
         result = func.apply(this, arguments);
-      } else {
+      }
+      if (n <= 1) {
         func = null;
       }
       return result;

function/bind.js

@@ -1,4 +1,4 @@
-define(['../internal/baseSlice', '../internal/createWrapper', '../internal/replaceHolders'], function(baseSlice, createWrapper, replaceHolders) {
+define(['../internal/createWrapper', '../internal/replaceHolders', './restParam'], function(createWrapper, replaceHolders, restParam) {
 
   /** Used to compose bitmasks for wrapper metadata. */
   var BIND_FLAG = 1,
@@ -12,7 +12,7 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    * The `_.bind.placeholder` value, which defaults to `_` in monolithic builds,
    * may be used as a placeholder for partially applied arguments.
    *
-   * **Note:** Unlike native `Function#bind` this method does not set the `length`
+   * **Note:** Unlike native `Function#bind` this method does not set the "length"
    * property of bound functions.
    *
    * @static
@@ -20,7 +20,7 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    * @category Function
    * @param {Function} func The function to bind.
    * @param {*} thisArg The `this` binding of `func`.
-   * @param {...*} [args] The arguments to be partially applied.
+   * @param {...*} [partials] The arguments to be partially applied.
    * @returns {Function} Returns the new bound function.
    * @example
    *
@@ -39,16 +39,14 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    * bound('hi');
    * // => 'hi fred!'
    */
-  function bind(func, thisArg) {
+  var bind = restParam(function(func, thisArg, partials) {
     var bitmask = BIND_FLAG;
-    if (arguments.length > 2) {
-      var partials = baseSlice(arguments, 2),
-          holders = replaceHolders(partials, bind.placeholder);
-
+    if (partials.length) {
+      var holders = replaceHolders(partials, bind.placeholder);
       bitmask |= PARTIAL_FLAG;
     }
     return createWrapper(func, bitmask, thisArg, partials, holders);
-  }
+  });
 
   // Assign default placeholders.
   bind.placeholder = {};

function/bindAll.js

@@ -1,4 +1,7 @@
-define(['../internal/baseBindAll', '../internal/baseFlatten', '../object/functions'], function(baseBindAll, baseFlatten, functions) {
+define(['../internal/baseFlatten', '../internal/createWrapper', '../object/functions', './restParam'], function(baseFlatten, createWrapper, functions, restParam) {
+
+  /** Used to compose bitmasks for wrapper metadata. */
+  var BIND_FLAG = 1;
 
   /**
    * Binds methods of an object to the object itself, overwriting the existing
@@ -6,7 +9,7 @@ define(['../internal/baseBindAll', '../internal/baseFlatten', '../object/functio
    * of method names. If no method names are provided all enumerable function
    * properties, own and inherited, of `object` are bound.
    *
-   * **Note:** This method does not set the `length` property of bound functions.
+   * **Note:** This method does not set the "length" property of bound functions.
    *
    * @static
    * @memberOf _
@@ -28,13 +31,18 @@ define(['../internal/baseBindAll', '../internal/baseFlatten', '../object/functio
    * jQuery('#docs').on('click', view.onClick);
    * // => logs 'clicked docs' when the element is clicked
    */
-  function bindAll(object) {
-    return baseBindAll(object,
-      arguments.length > 1
-        ? baseFlatten(arguments, false, false, 1)
-        : functions(object)
-    );
-  }
+  var bindAll = restParam(function(object, methodNames) {
+    methodNames = methodNames.length ? baseFlatten(methodNames) : functions(object);
+
+    var index = -1,
+        length = methodNames.length;
+
+    while (++index < length) {
+      var key = methodNames[index];
+      object[key] = createWrapper(object[key], BIND_FLAG, object);
+    }
+    return object;
+  });
 
   return bindAll;
 });

function/bindKey.js

@@ -1,4 +1,4 @@
-define(['../internal/baseSlice', '../internal/createWrapper', '../internal/replaceHolders'], function(baseSlice, createWrapper, replaceHolders) {
+define(['../internal/createWrapper', '../internal/replaceHolders', './restParam'], function(createWrapper, replaceHolders, restParam) {
 
   /** Used to compose bitmasks for wrapper metadata. */
   var BIND_FLAG = 1,
@@ -11,7 +11,7 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    *
    * This method differs from `_.bind` by allowing bound functions to reference
    * methods that may be redefined or don't yet exist.
-   * See [Peter Michaux's article](http://michaux.ca/articles/lazy-function-definition-pattern)
+   * See [Peter Michaux's article](http://peter.michaux.ca/articles/lazy-function-definition-pattern)
    * for more details.
    *
    * The `_.bindKey.placeholder` value, which defaults to `_` in monolithic
@@ -22,7 +22,7 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    * @category Function
    * @param {Object} object The object the method belongs to.
    * @param {string} key The key of the method.
-   * @param {...*} [args] The arguments to be partially applied.
+   * @param {...*} [partials] The arguments to be partially applied.
    * @returns {Function} Returns the new bound function.
    * @example
    *
@@ -49,16 +49,14 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    * bound('hi');
    * // => 'hiya fred!'
    */
-  function bindKey(object, key) {
+  var bindKey = restParam(function(object, key, partials) {
     var bitmask = BIND_FLAG | BIND_KEY_FLAG;
-    if (arguments.length > 2) {
-      var partials = baseSlice(arguments, 2),
-          holders = replaceHolders(partials, bindKey.placeholder);
-
+    if (partials.length) {
+      var holders = replaceHolders(partials, bindKey.placeholder);
       bitmask |= PARTIAL_FLAG;
     }
     return createWrapper(key, bitmask, object, partials, holders);
-  }
+  });
 
   // Assign default placeholders.
   bindKey.placeholder = {};

function/curry.js

@@ -1,4 +1,4 @@
-define(['../internal/createWrapper', '../internal/isIterateeCall'], function(createWrapper, isIterateeCall) {
+define(['../internal/createCurry'], function(createCurry) {
 
   /** Used to compose bitmasks for wrapper metadata. */
   var CURRY_FLAG = 8;
@@ -13,7 +13,7 @@ define(['../internal/createWrapper', '../internal/isIterateeCall'], function(cre
    * The `_.curry.placeholder` value, which defaults to `_` in monolithic builds,
    * may be used as a placeholder for provided arguments.
    *
-   * **Note:** This method does not set the `length` property of curried functions.
+   * **Note:** This method does not set the "length" property of curried functions.
    *
    * @static
    * @memberOf _
@@ -43,14 +43,7 @@ define(['../internal/createWrapper', '../internal/isIterateeCall'], function(cre
    * curried(1)(_, 3)(2);
    * // => [1, 2, 3]
    */
-  function curry(func, arity, guard) {
-    if (guard && isIterateeCall(func, arity, guard)) {
-      arity = null;
-    }
-    var result = createWrapper(func, CURRY_FLAG, null, null, null, null, null, arity);
-    result.placeholder = curry.placeholder;
-    return result;
-  }
+  var curry = createCurry(CURRY_FLAG);
 
   // Assign default placeholders.
   curry.placeholder = {};

function/curryRight.js

@@ -1,4 +1,4 @@
-define(['../internal/createWrapper', '../internal/isIterateeCall'], function(createWrapper, isIterateeCall) {
+define(['../internal/createCurry'], function(createCurry) {
 
   /** Used to compose bitmasks for wrapper metadata. */
   var CURRY_RIGHT_FLAG = 16;
@@ -10,7 +10,7 @@ define(['../internal/createWrapper', '../internal/isIterateeCall'], function(cre
    * The `_.curryRight.placeholder` value, which defaults to `_` in monolithic
    * builds, may be used as a placeholder for provided arguments.
    *
-   * **Note:** This method does not set the `length` property of curried functions.
+   * **Note:** This method does not set the "length" property of curried functions.
    *
    * @static
    * @memberOf _
@@ -40,14 +40,7 @@ define(['../internal/createWrapper', '../internal/isIterateeCall'], function(cre
    * curried(3)(1, _)(2);
    * // => [1, 2, 3]
    */
-  function curryRight(func, arity, guard) {
-    if (guard && isIterateeCall(func, arity, guard)) {
-      arity = null;
-    }
-    var result = createWrapper(func, CURRY_RIGHT_FLAG, null, null, null, null, null, arity);
-    result.placeholder = curryRight.placeholder;
-    return result;
-  }
+  var curryRight = createCurry(CURRY_RIGHT_FLAG);
 
   // Assign default placeholders.
   curryRight.placeholder = {};

function/defer.js

@@ -1,4 +1,4 @@
-define(['../internal/baseDelay'], function(baseDelay) {
+define(['../internal/baseDelay', './restParam'], function(baseDelay, restParam) {
 
   /**
    * Defers invoking the `func` until the current call stack has cleared. Any
@@ -17,9 +17,9 @@ define(['../internal/baseDelay'], function(baseDelay) {
    * }, 'deferred');
    * // logs 'deferred' after one or more milliseconds
    */
-  function defer(func) {
-    return baseDelay(func, 1, arguments, 1);
-  }
+  var defer = restParam(function(func, args) {
+    return baseDelay(func, 1, args);
+  });
 
   return defer;
 });

function/delay.js

@@ -1,4 +1,4 @@
-define(['../internal/baseDelay'], function(baseDelay) {
+define(['../internal/baseDelay', './restParam'], function(baseDelay, restParam) {
 
   /**
    * Invokes `func` after `wait` milliseconds. Any additional arguments are
@@ -18,9 +18,9 @@ define(['../internal/baseDelay'], function(baseDelay) {
    * }, 1000, 'later');
    * // => logs 'later' after one second
    */
-  function delay(func, wait) {
-    return baseDelay(func, wait, arguments, 2);
-  }
+  var delay = restParam(function(func, wait, args) {
+    return baseDelay(func, wait, args);
+  });
 
   return delay;
 });

function/flow.js

@@ -1,4 +1,4 @@
-define(['../internal/createComposer'], function(createComposer) {
+define(['../internal/createFlow'], function(createFlow) {
 
   /**
    * Creates a function that returns the result of invoking the provided
@@ -20,7 +20,7 @@ define(['../internal/createComposer'], function(createComposer) {
    * addSquare(1, 2);
    * // => 9
    */
-  var flow = createComposer();
+  var flow = createFlow();
 
   return flow;
 });

function/flowRight.js

@@ -1,4 +1,4 @@
-define(['../internal/createComposer'], function(createComposer) {
+define(['../internal/createFlow'], function(createFlow) {
 
   /**
    * This method is like `_.flow` except that it creates a function that
@@ -20,7 +20,7 @@ define(['../internal/createComposer'], function(createComposer) {
    * addSquare(1, 2);
    * // => 9
    */
-  var flowRight = createComposer(true);
+  var flowRight = createFlow(true);
 
   return flowRight;
 });

function/memoize.js

@@ -13,10 +13,8 @@ define(['../internal/MapCache'], function(MapCache) {
    *
    * **Note:** The cache is exposed as the `cache` property on the memoized
    * function. Its creation may be customized by replacing the `_.memoize.Cache`
-   * constructor with one whose instances implement the ES `Map` method interface
-   * of `get`, `has`, and `set`. See the
-   * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-properties-of-the-map-prototype-object)
-   * for more details.
+   * constructor with one whose instances implement the [`Map`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-properties-of-the-map-prototype-object)
+   * method interface of `get`, `has`, and `set`.
    *
    * @static
    * @memberOf _

function/once.js

@@ -3,7 +3,7 @@ define(['./before'], function(before) {
   /**
    * Creates a function that is restricted to invoking `func` once. Repeat calls
    * to the function return the value of the first call. The `func` is invoked
-   * with the `this` binding of the created function.
+   * with the `this` binding and arguments of the created function.
    *
    * @static
    * @memberOf _
@@ -18,7 +18,7 @@ define(['./before'], function(before) {
    * // `initialize` invokes `createApplication` once
    */
   function once(func) {
-    return before(func, 2);
+    return before(2, func);
   }
 
   return once;

function/partial.js

@@ -1,4 +1,4 @@
-define(['../internal/baseSlice', '../internal/createWrapper', '../internal/replaceHolders'], function(baseSlice, createWrapper, replaceHolders) {
+define(['../internal/createPartial'], function(createPartial) {
 
   /** Used to compose bitmasks for wrapper metadata. */
   var PARTIAL_FLAG = 32;
@@ -11,14 +11,14 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    * The `_.partial.placeholder` value, which defaults to `_` in monolithic
    * builds, may be used as a placeholder for partially applied arguments.
    *
-   * **Note:** This method does not set the `length` property of partially
+   * **Note:** This method does not set the "length" property of partially
    * applied functions.
    *
    * @static
    * @memberOf _
    * @category Function
    * @param {Function} func The function to partially apply arguments to.
-   * @param {...*} [args] The arguments to be partially applied.
+   * @param {...*} [partials] The arguments to be partially applied.
    * @returns {Function} Returns the new partially applied function.
    * @example
    *
@@ -35,12 +35,7 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    * greetFred('hi');
    * // => 'hi fred'
    */
-  function partial(func) {
-    var partials = baseSlice(arguments, 1),
-        holders = replaceHolders(partials, partial.placeholder);
-
-    return createWrapper(func, PARTIAL_FLAG, null, partials, holders);
-  }
+  var partial = createPartial(PARTIAL_FLAG);
 
   // Assign default placeholders.
   partial.placeholder = {};

function/partialRight.js

@@ -1,4 +1,4 @@
-define(['../internal/baseSlice', '../internal/createWrapper', '../internal/replaceHolders'], function(baseSlice, createWrapper, replaceHolders) {
+define(['../internal/createPartial'], function(createPartial) {
 
   /** Used to compose bitmasks for wrapper metadata. */
   var PARTIAL_RIGHT_FLAG = 64;
@@ -10,14 +10,14 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    * The `_.partialRight.placeholder` value, which defaults to `_` in monolithic
    * builds, may be used as a placeholder for partially applied arguments.
    *
-   * **Note:** This method does not set the `length` property of partially
+   * **Note:** This method does not set the "length" property of partially
    * applied functions.
    *
    * @static
    * @memberOf _
    * @category Function
    * @param {Function} func The function to partially apply arguments to.
-   * @param {...*} [args] The arguments to be partially applied.
+   * @param {...*} [partials] The arguments to be partially applied.
    * @returns {Function} Returns the new partially applied function.
    * @example
    *
@@ -34,12 +34,7 @@ define(['../internal/baseSlice', '../internal/createWrapper', '../internal/repla
    * sayHelloTo('fred');
    * // => 'hello fred'
    */
-  function partialRight(func) {
-    var partials = baseSlice(arguments, 1),
-        holders = replaceHolders(partials, partialRight.placeholder);
-
-    return createWrapper(func, PARTIAL_RIGHT_FLAG, null, partials, holders);
-  }
+  var partialRight = createPartial(PARTIAL_RIGHT_FLAG);
 
   // Assign default placeholders.
   partialRight.placeholder = {};

function/rearg.js

@@ -1,7 +1,7 @@
-define(['../internal/baseFlatten', '../internal/createWrapper'], function(baseFlatten, createWrapper) {
+define(['../internal/baseFlatten', '../internal/createWrapper', './restParam'], function(baseFlatten, createWrapper, restParam) {
 
   /** Used to compose bitmasks for wrapper metadata. */
-  var REARG_FLAG = 128;
+  var REARG_FLAG = 256;
 
   /**
    * Creates a function that invokes `func` with arguments arranged according
@@ -31,10 +31,9 @@ define(['../internal/baseFlatten', '../internal/createWrapper'], function(baseFl
    * }, [1, 2, 3]);
    * // => [3, 6, 9]
    */
-  function rearg(func) {
-    var indexes = baseFlatten(arguments, false, false, 1);
-    return createWrapper(func, REARG_FLAG, null, null, null, indexes);
-  }
+  var rearg = restParam(function(func, indexes) {
+    return createWrapper(func, REARG_FLAG, null, null, null, baseFlatten(indexes));
+  });
 
   return rearg;
 });

function/restParam.js

@@ -0,0 +1,64 @@
+define([], function() {
+
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
+
+  /** Used as the `TypeError` message for "Functions" methods. */
+  var FUNC_ERROR_TEXT = 'Expected a function';
+
+  /* Native method references for those with the same name as other `lodash` methods. */
+  var nativeMax = Math.max;
+
+  /**
+   * Creates a function that invokes `func` with the `this` binding of the
+   * created function and arguments from `start` and beyond provided as an array.
+   *
+   * **Note:** This method is based on the [rest parameter](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters).
+   *
+   * @static
+   * @memberOf _
+   * @category Function
+   * @param {Function} func The function to apply a rest parameter to.
+   * @param {number} [start=func.length-1] The start position of the rest parameter.
+   * @returns {Function} Returns the new function.
+   * @example
+   *
+   * var say = _.restParam(function(what, names) {
+   *   return what + ' ' + _.initial(names).join(', ') +
+   *     (_.size(names) > 1 ? ', & ' : '') + _.last(names);
+   * });
+   *
+   * say('hello', 'fred', 'barney', 'pebbles');
+   * // => 'hello fred, barney, & pebbles'
+   */
+  function restParam(func, start) {
+    if (typeof func != 'function') {
+      throw new TypeError(FUNC_ERROR_TEXT);
+    }
+    start = nativeMax(start === undefined ? (func.length - 1) : (+start || 0), 0);
+    return function() {
+      var args = arguments,
+          index = -1,
+          length = nativeMax(args.length - start, 0),
+          rest = Array(length);
+
+      while (++index < length) {
+        rest[index] = args[start + index];
+      }
+      switch (start) {
+        case 0: return func.call(this, rest);
+        case 1: return func.call(this, args[0], rest);
+        case 2: return func.call(this, args[0], args[1], rest);
+      }
+      var otherArgs = Array(start + 1);
+      index = -1;
+      while (++index < start) {
+        otherArgs[index] = args[index];
+      }
+      otherArgs[start] = rest;
+      return func.apply(this, otherArgs);
+    };
+  }
+
+  return restParam;
+});

function/spread.js

@@ -4,23 +4,24 @@ define([], function() {
   var FUNC_ERROR_TEXT = 'Expected a function';
 
   /**
-   * Creates a function that invokes `func` with the `this` binding of the
-   * created function and the array of arguments provided to the created
-   * function much like [Function#apply](http://es5.github.io/#x15.3.4.3).
+   * Creates a function that invokes `func` with the `this` binding of the created
+   * function and an array of arguments much like [`Function#apply`](https://es5.github.io/#x15.3.4.3).
+   *
+   * **Note:** This method is based on the [spread operator](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_operator).
    *
    * @static
    * @memberOf _
    * @category Function
    * @param {Function} func The function to spread arguments over.
-   * @returns {*} Returns the new function.
+   * @returns {Function} Returns the new function.
    * @example
    *
-   * var spread = _.spread(function(who, what) {
+   * var say = _.spread(function(who, what) {
    *   return who + ' says ' + what;
    * });
    *
-   * spread(['Fred', 'hello']);
-   * // => 'Fred says hello'
+   * say(['fred', 'hello']);
+   * // => 'fred says hello'
    *
    * // with a Promise
    * var numbers = Promise.all([

internal/arrayEach.js

@@ -2,7 +2,7 @@ define([], function() {
 
   /**
    * A specialized version of `_.forEach` for arrays without support for callback
-   * shorthands or `this` binding.
+   * shorthands and `this` binding.
    *
    * @private
    * @param {Array} array The array to iterate over.

internal/arrayEachRight.js

@@ -2,7 +2,7 @@ define([], function() {
 
   /**
    * A specialized version of `_.forEachRight` for arrays without support for
-   * callback shorthands or `this` binding.
+   * callback shorthands and `this` binding.
    *
    * @private
    * @param {Array} array The array to iterate over.

internal/arrayEvery.js

@@ -2,7 +2,7 @@ define([], function() {
 
   /**
    * A specialized version of `_.every` for arrays without support for callback
-   * shorthands or `this` binding.
+   * shorthands and `this` binding.
    *
    * @private
    * @param {Array} array The array to iterate over.

internal/arrayFilter.js

@@ -2,7 +2,7 @@ define([], function() {
 
   /**
    * A specialized version of `_.filter` for arrays without support for callback
-   * shorthands or `this` binding.
+   * shorthands and `this` binding.
    *
    * @private
    * @param {Array} array The array to iterate over.

internal/arrayMap.js

@@ -2,7 +2,7 @@ define([], function() {
 
   /**
    * A specialized version of `_.map` for arrays without support for callback
-   * shorthands or `this` binding.
+   * shorthands and `this` binding.
    *
    * @private
    * @param {Array} array The array to iterate over.

internal/arrayReduce.js

@@ -2,7 +2,7 @@ define([], function() {
 
   /**
    * A specialized version of `_.reduce` for arrays without support for callback
-   * shorthands or `this` binding.
+   * shorthands and `this` binding.
    *
    * @private
    * @param {Array} array The array to iterate over.

internal/arrayReduceRight.js

@@ -2,7 +2,7 @@ define([], function() {
 
   /**
    * A specialized version of `_.reduceRight` for arrays without support for
-   * callback shorthands or `this` binding.
+   * callback shorthands and `this` binding.
    *
    * @private
    * @param {Array} array The array to iterate over.

internal/arraySome.js

@@ -2,7 +2,7 @@ define([], function() {
 
   /**
    * A specialized version of `_.some` for arrays without support for callback
-   * shorthands or `this` binding.
+   * shorthands and `this` binding.
    *
    * @private
    * @param {Array} array The array to iterate over.

internal/arraySum.js

@@ -0,0 +1,21 @@
+define([], function() {
+
+  /**
+   * A specialized version of `_.sum` for arrays without support for iteratees.
+   *
+   * @private
+   * @param {Array} array The array to iterate over.
+   * @returns {number} Returns the sum.
+   */
+  function arraySum(array) {
+    var length = array.length,
+        result = 0;
+
+    while (length--) {
+      result += +array[length] || 0;
+    }
+    return result;
+  }
+
+  return arraySum;
+});

internal/assignDefaults.js

@@ -1,5 +1,8 @@
 define([], function() {
 
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
+
   /**
    * Used by `_.defaults` to customize its `_.assign` use.
    *
@@ -9,7 +12,7 @@ define([], function() {
    * @returns {*} Returns the value to assign to the destination object.
    */
   function assignDefaults(objectValue, sourceValue) {
-    return typeof objectValue == 'undefined' ? sourceValue : objectValue;
+    return objectValue === undefined ? sourceValue : objectValue;
   }
 
   return assignDefaults;

internal/assignOwnDefaults.js

@@ -1,5 +1,8 @@
 define([], function() {
 
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
+
   /** Used for native method references. */
   var objectProto = Object.prototype;
 
@@ -9,7 +12,7 @@ define([], function() {
   /**
    * Used by `_.template` to customize its `_.assign` use.
    *
-   * **Note:** This method is like `assignDefaults` except that it ignores
+   * **Note:** This function is like `assignDefaults` except that it ignores
    * inherited property values when checking if a property is `undefined`.
    *
    * @private
@@ -20,7 +23,7 @@ define([], function() {
    * @returns {*} Returns the value to assign to the destination object.
    */
   function assignOwnDefaults(objectValue, sourceValue, key, object) {
-    return (typeof objectValue == 'undefined' || !hasOwnProperty.call(object, key))
+    return (objectValue === undefined || !hasOwnProperty.call(object, key))
       ? sourceValue
       : objectValue;
   }

internal/assignWith.js

@@ -0,0 +1,44 @@
+define(['./getSymbols', '../object/keys'], function(getSymbols, keys) {
+
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
+
+  /** Used for native method references. */
+  var arrayProto = Array.prototype;
+
+  /** Native method references. */
+  var push = arrayProto.push;
+
+  /**
+   * A specialized version of `_.assign` for customizing assigned values without
+   * support for argument juggling, multiple sources, and `this` binding `customizer`
+   * functions.
+   *
+   * @private
+   * @param {Object} object The destination object.
+   * @param {Object} source The source object.
+   * @param {Function} customizer The function to customize assigned values.
+   * @returns {Object} Returns `object`.
+   */
+  function assignWith(object, source, customizer) {
+    var props = keys(source);
+    push.apply(props, getSymbols(source));
+
+    var index = -1,
+        length = props.length;
+
+    while (++index < length) {
+      var key = props[index],
+          value = object[key],
+          result = customizer(value, source[key], key, object, source);
+
+      if ((result === result ? (result !== value) : (value === value)) ||
+          (value === undefined && !(key in object))) {
+        object[key] = result;
+      }
+    }
+    return object;
+  }
+
+  return assignWith;
+});

internal/baseAssign.js

@@ -1,35 +1,45 @@
-define(['./baseCopy', '../object/keys'], function(baseCopy, keys) {
+define(['./baseCopy', './getSymbols', '../lang/isNative', '../object/keys'], function(baseCopy, getSymbols, isNative, keys) {
+
+  /** Native method references. */
+  var preventExtensions = isNative(preventExtensions = Object.preventExtensions) && preventExtensions;
+
+  /** Used as `baseAssign`. */
+  var nativeAssign = (function() {
+    // Avoid `Object.assign` in Firefox 34-37 which have an early implementation
+    // with a now defunct try/catch behavior. See https://bugzilla.mozilla.org/show_bug.cgi?id=1103344
+    // for more details.
+    //
+    // Use `Object.preventExtensions` on a plain object instead of simply using
+    // `Object('x')` because Chrome and IE fail to throw an error when attempting
+    // to assign values to readonly indexes of strings.
+    var func = preventExtensions && isNative(func = Object.assign) && func;
+    try {
+      if (func) {
+        var object = preventExtensions({ '1': 0 });
+        object[0] = 1;
+      }
+    } catch(e) {
+      // Only attempt in strict mode.
+      try { func(object, 'xo'); } catch(e) {}
+      return !object[1] && func;
+    }
+    return false;
+  }());
 
   /**
    * The base implementation of `_.assign` without support for argument juggling,
-   * multiple sources, and `this` binding `customizer` functions.
+   * multiple sources, and `customizer` functions.
    *
    * @private
    * @param {Object} object The destination object.
    * @param {Object} source The source object.
-   * @param {Function} [customizer] The function to customize assigning values.
-   * @returns {Object} Returns the destination object.
+   * @returns {Object} Returns `object`.
    */
-  function baseAssign(object, source, customizer) {
-    var props = keys(source);
-    if (!customizer) {
-      return baseCopy(source, object, props);
-    }
-    var index = -1,
-        length = props.length;
-
-    while (++index < length) {
-      var key = props[index],
-          value = object[key],
-          result = customizer(value, source[key], key, object, source);
-
-      if ((result === result ? result !== value : value === value) ||
-          (typeof value == 'undefined' && !(key in object))) {
-        object[key] = result;
-      }
-    }
-    return object;
-  }
+  var baseAssign = nativeAssign || function(object, source) {
+    return source == null
+      ? object
+      : baseCopy(source, getSymbols(source), baseCopy(source, keys(source), object));
+  };
 
   return baseAssign;
 });

internal/baseAt.js

@@ -1,31 +1,31 @@
-define(['./isIndex', './isLength'], function(isIndex, isLength) {
+define(['./isArrayLike', './isIndex'], function(isArrayLike, isIndex) {
 
   /** Used as a safe reference for `undefined` in pre-ES5 environments. */
   var undefined;
 
   /**
-   * The base implementation of `_.at` without support for strings and individual
-   * key arguments.
+   * The base implementation of `_.at` without support for string collections
+   * and individual key arguments.
    *
    * @private
    * @param {Array|Object} collection The collection to iterate over.
-   * @param {number[]|string[]} [props] The property names or indexes of elements to pick.
+   * @param {number[]|string[]} props The property names or indexes of elements to pick.
    * @returns {Array} Returns the new array of picked elements.
    */
   function baseAt(collection, props) {
     var index = -1,
-        length = collection.length,
-        isArr = isLength(length),
+        isNil = collection == null,
+        isArr = !isNil && isArrayLike(collection),
+        length = isArr && collection.length,
         propsLength = props.length,
         result = Array(propsLength);
 
     while(++index < propsLength) {
       var key = props[index];
       if (isArr) {
-        key = parseFloat(key);
         result[index] = isIndex(key, length) ? collection[key] : undefined;
       } else {
-        result[index] = collection[key];
+        result[index] = isNil ? undefined : collection[key];
       }
     }
     return result;

internal/baseBindAll.js

@@ -1,27 +0,0 @@
-define(['./createWrapper'], function(createWrapper) {
-
-  /** Used to compose bitmasks for wrapper metadata. */
-  var BIND_FLAG = 1;
-
-  /**
-   * The base implementation of `_.bindAll` without support for individual
-   * method name arguments.
-   *
-   * @private
-   * @param {Object} object The object to bind and assign the bound methods to.
-   * @param {string[]} methodNames The object method names to bind.
-   * @returns {Object} Returns `object`.
-   */
-  function baseBindAll(object, methodNames) {
-    var index = -1,
-        length = methodNames.length;
-
-    while (++index < length) {
-      var key = methodNames[index];
-      object[key] = createWrapper(object[key], BIND_FLAG, object);
-    }
-    return object;
-  }
-
-  return baseBindAll;
-});

internal/baseCallback.js

@@ -1,4 +1,7 @@
-define(['./baseMatches', './baseMatchesProperty', './baseProperty', './bindCallback', '../utility/identity', './isBindable'], function(baseMatches, baseMatchesProperty, baseProperty, bindCallback, identity, isBindable) {
+define(['./baseMatches', './baseMatchesProperty', './bindCallback', '../utility/identity', '../utility/property'], function(baseMatches, baseMatchesProperty, bindCallback, identity, property) {
+
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
 
   /**
    * The base implementation of `_.callback` which supports specifying the
@@ -13,9 +16,9 @@ define(['./baseMatches', './baseMatchesProperty', './baseProperty', './bindCallb
   function baseCallback(func, thisArg, argCount) {
     var type = typeof func;
     if (type == 'function') {
-      return (typeof thisArg != 'undefined' && isBindable(func))
-        ? bindCallback(func, thisArg, argCount)
-        : func;
+      return thisArg === undefined
+        ? func
+        : bindCallback(func, thisArg, argCount);
     }
     if (func == null) {
       return identity;
@@ -23,9 +26,9 @@ define(['./baseMatches', './baseMatchesProperty', './baseProperty', './bindCallb
     if (type == 'object') {
       return baseMatches(func);
     }
-    return typeof thisArg == 'undefined'
-      ? baseProperty(func + '')
-      : baseMatchesProperty(func + '', thisArg);
+    return thisArg === undefined
+      ? property(func)
+      : baseMatchesProperty(func, thisArg);
   }
 
   return baseCallback;

internal/baseClone.js

@@ -1,4 +1,7 @@
-define(['./arrayCopy', './arrayEach', './baseCopy', './baseForOwn', './initCloneArray', './initCloneByTag', './initCloneObject', '../lang/isArray', '../lang/isObject', '../object/keys'], function(arrayCopy, arrayEach, baseCopy, baseForOwn, initCloneArray, initCloneByTag, initCloneObject, isArray, isObject, keys) {
+define(['./arrayCopy', './arrayEach', './baseAssign', './baseForOwn', './initCloneArray', './initCloneByTag', './initCloneObject', '../lang/isArray', '../lang/isObject'], function(arrayCopy, arrayEach, baseAssign, baseForOwn, initCloneArray, initCloneByTag, initCloneObject, isArray, isObject) {
+
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
 
   /** `Object#toString` result references. */
   var argsTag = '[object Arguments]',
@@ -45,9 +48,8 @@ define(['./arrayCopy', './arrayEach', './baseCopy', './baseForOwn', './initClone
   var objectProto = Object.prototype;
 
   /**
-   * Used to resolve the `toStringTag` of values.
-   * See the [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-object.prototype.tostring)
-   * for more details.
+   * Used to resolve the [`toStringTag`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-object.prototype.tostring)
+   * of values.
    */
   var objToString = objectProto.toString;
 
@@ -70,7 +72,7 @@ define(['./arrayCopy', './arrayEach', './baseCopy', './baseForOwn', './initClone
     if (customizer) {
       result = object ? customizer(value, key, object) : customizer(value);
     }
-    if (typeof result != 'undefined') {
+    if (result !== undefined) {
       return result;
     }
     if (!isObject(value)) {
@@ -89,7 +91,7 @@ define(['./arrayCopy', './arrayEach', './baseCopy', './baseForOwn', './initClone
       if (tag == objectTag || tag == argsTag || (isFunc && !object)) {
         result = initCloneObject(isFunc ? {} : value);
         if (!isDeep) {
-          return baseCopy(value, result, keys(value));
+          return baseAssign(result, value);
         }
       } else {
         return cloneableTags[tag]

internal/baseCompareAscending.js

@@ -1,5 +1,8 @@
 define([], function() {
 
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
+
   /**
    * The base implementation of `compareAscending` which compares values and
    * sorts them in ascending order without guaranteeing a stable sort.
@@ -14,10 +17,10 @@ define([], function() {
       var valIsReflexive = value === value,
           othIsReflexive = other === other;
 
-      if (value > other || !valIsReflexive || (typeof value == 'undefined' && othIsReflexive)) {
+      if (value > other || !valIsReflexive || (value === undefined && othIsReflexive)) {
         return 1;
       }
-      if (value < other || !othIsReflexive || (typeof other == 'undefined' && valIsReflexive)) {
+      if (value < other || !othIsReflexive || (other === undefined && valIsReflexive)) {
         return -1;
       }
     }

internal/baseCopy.js

@@ -1,19 +1,17 @@
 define([], function() {
 
   /**
-   * Copies the properties of `source` to `object`.
+   * Copies properties of `source` to `object`.
    *
    * @private
    * @param {Object} source The object to copy properties from.
-   * @param {Object} [object={}] The object to copy properties to.
    * @param {Array} props The property names to copy.
+   * @param {Object} [object={}] The object to copy properties to.
    * @returns {Object} Returns `object`.
    */
-  function baseCopy(source, object, props) {
-    if (!props) {
-      props = object;
-      object = {};
-    }
+  function baseCopy(source, props, object) {
+    object || (object = {});
+
     var index = -1,
         length = props.length;
 

internal/baseDelay.js

@@ -1,4 +1,4 @@
-define(['./baseSlice'], function(baseSlice) {
+define([], function() {
 
   /** Used as a safe reference for `undefined` in pre-ES5 environments. */
   var undefined;
@@ -13,14 +13,14 @@ define(['./baseSlice'], function(baseSlice) {
    * @private
    * @param {Function} func The function to delay.
    * @param {number} wait The number of milliseconds to delay invocation.
-   * @param {Object} args The `arguments` object to slice and provide to `func`.
+   * @param {Object} args The arguments provide to `func`.
    * @returns {number} Returns the timer id.
    */
-  function baseDelay(func, wait, args, fromIndex) {
+  function baseDelay(func, wait, args) {
     if (typeof func != 'function') {
       throw new TypeError(FUNC_ERROR_TEXT);
     }
-    return setTimeout(function() { func.apply(undefined, baseSlice(args, fromIndex)); }, wait);
+    return setTimeout(function() { func.apply(undefined, args); }, wait);
   }
 
   return baseDelay;

internal/baseEach.js

@@ -1,4 +1,4 @@
-define(['./baseForOwn', './isLength', './toObject'], function(baseForOwn, isLength, toObject) {
+define(['./baseForOwn', './createBaseEach'], function(baseForOwn, createBaseEach) {
 
   /**
    * The base implementation of `_.forEach` without support for callback
@@ -9,21 +9,7 @@ define(['./baseForOwn', './isLength', './toObject'], function(baseForOwn, isLeng
    * @param {Function} iteratee The function invoked per iteration.
    * @returns {Array|Object|string} Returns `collection`.
    */
-  function baseEach(collection, iteratee) {
-    var length = collection ? collection.length : 0;
-    if (!isLength(length)) {
-      return baseForOwn(collection, iteratee);
-    }
-    var index = -1,
-        iterable = toObject(collection);
-
-    while (++index < length) {
-      if (iteratee(iterable[index], index, iterable) === false) {
-        break;
-      }
-    }
-    return collection;
-  }
+  var baseEach = createBaseEach(baseForOwn);
 
   return baseEach;
 });

internal/baseEachRight.js

@@ -1,4 +1,4 @@
-define(['./baseForOwnRight', './isLength', './toObject'], function(baseForOwnRight, isLength, toObject) {
+define(['./baseForOwnRight', './createBaseEach'], function(baseForOwnRight, createBaseEach) {
 
   /**
    * The base implementation of `_.forEachRight` without support for callback
@@ -9,19 +9,7 @@ define(['./baseForOwnRight', './isLength', './toObject'], function(baseForOwnRig
    * @param {Function} iteratee The function invoked per iteration.
    * @returns {Array|Object|string} Returns `collection`.
    */
-  function baseEachRight(collection, iteratee) {
-    var length = collection ? collection.length : 0;
-    if (!isLength(length)) {
-      return baseForOwnRight(collection, iteratee);
-    }
-    var iterable = toObject(collection);
-    while (length--) {
-      if (iteratee(iterable[length], length, iterable) === false) {
-        break;
-      }
-    }
-    return collection;
-  }
+  var baseEachRight = createBaseEach(baseForOwnRight, true);
 
   return baseEachRight;
 });

internal/baseEvery.js

@@ -2,7 +2,7 @@ define(['./baseEach'], function(baseEach) {
 
   /**
    * The base implementation of `_.every` without support for callback
-   * shorthands or `this` binding.
+   * shorthands and `this` binding.
    *
    * @private
    * @param {Array|Object|string} collection The collection to iterate over.

internal/baseFill.js

@@ -1,5 +1,8 @@
 define([], function() {
 
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
+
   /**
    * The base implementation of `_.fill` without an iteratee call guard.
    *
@@ -17,11 +20,11 @@ define([], function() {
     if (start < 0) {
       start = -start > length ? 0 : (length + start);
     }
-    end = (typeof end == 'undefined' || end > length) ? length : (+end || 0);
+    end = (end === undefined || end > length) ? length : (+end || 0);
     if (end < 0) {
       end += length;
     }
-    length = start > end ? 0 : end >>> 0;
+    length = start > end ? 0 : (end >>> 0);
     start >>>= 0;
 
     while (start < length) {

internal/baseFilter.js

@@ -2,7 +2,7 @@ define(['./baseEach'], function(baseEach) {
 
   /**
    * The base implementation of `_.filter` without support for callback
-   * shorthands or `this` binding.
+   * shorthands and `this` binding.
    *
    * @private
    * @param {Array|Object|string} collection The collection to iterate over.