Apply more let/const transforms.

_ListCache.js

@@ -12,12 +12,12 @@ import listCacheSet from './_listCacheSet.js';
  * @param {Array} [entries] The key-value pairs to cache.
  */
 function ListCache(entries) {
-  var index = -1,
+  let index = -1;
-      length = entries == null ? 0 : entries.length;
+  const length = entries == null ? 0 : entries.length;
 
   this.clear();
   while (++index < length) {
-    var entry = entries[index];
+    const entry = entries[index];
     this.set(entry[0], entry[1]);
   }
 }

_Map.js

@@ -2,6 +2,6 @@ import getNative from './_getNative.js';
 import root from './_root.js';
 
 /* Built-in method references that are verified to be native. */
-var Map = getNative(root, 'Map');
+const Map = getNative(root, 'Map');
 
 export default Map;

_MapCache.js

@@ -12,12 +12,12 @@ import mapCacheSet from './_mapCacheSet.js';
  * @param {Array} [entries] The key-value pairs to cache.
  */
 function MapCache(entries) {
-  var index = -1,
+  let index = -1;
-      length = entries == null ? 0 : entries.length;
+  const length = entries == null ? 0 : entries.length;
 
   this.clear();
   while (++index < length) {
-    var entry = entries[index];
+    const entry = entries[index];
     this.set(entry[0], entry[1]);
   }
 }

_Promise.js

@@ -2,6 +2,6 @@ import getNative from './_getNative.js';
 import root from './_root.js';
 
 /* Built-in method references that are verified to be native. */
-var Promise = getNative(root, 'Promise');
+const Promise = getNative(root, 'Promise');
 
 export default Promise;

_arrayLikeKeys.js

@@ -6,10 +6,10 @@ import isIndex from './_isIndex.js';
 import isTypedArray from './isTypedArray.js';
 
 /** Used for built-in method references. */
-var objectProto = Object.prototype;
+const objectProto = Object.prototype;
 
 /** Used to check objects for own properties. */
-var hasOwnProperty = objectProto.hasOwnProperty;
+const hasOwnProperty = objectProto.hasOwnProperty;
 
 /**
  * Creates an array of the enumerable property names of the array-like `value`.
@@ -20,15 +20,15 @@ var hasOwnProperty = objectProto.hasOwnProperty;
  * @returns {Array} Returns the array of property names.
  */
 function arrayLikeKeys(value, inherited) {
-  var isArr = isArray(value),
+  const isArr = isArray(value);
-      isArg = !isArr && isArguments(value),
+  const isArg = !isArr && isArguments(value);
-      isBuff = !isArr && !isArg && isBuffer(value),
+  const isBuff = !isArr && !isArg && isBuffer(value);
-      isType = !isArr && !isArg && !isBuff && isTypedArray(value),
+  const isType = !isArr && !isArg && !isBuff && isTypedArray(value);
-      skipIndexes = isArr || isArg || isBuff || isType,
+  const skipIndexes = isArr || isArg || isBuff || isType;
-      result = skipIndexes ? baseTimes(value.length, String) : [],
+  const result = skipIndexes ? baseTimes(value.length, String) : [];
-      length = result.length;
+  const length = result.length;
 
-  for (var key in value) {
+  for (const key in value) {
     if ((inherited || hasOwnProperty.call(value, key)) &&
         !(skipIndexes && (
            // Safari 9 has enumerable `arguments.length` in strict mode.

_baseClone.js

@@ -24,36 +24,36 @@ const CLONE_FLAT_FLAG = 2;
 const CLONE_SYMBOLS_FLAG = 4;
 
 /** `Object#toString` result references. */
-const argsTag = '[object Arguments]',
+const argsTag = '[object Arguments]';
-    arrayTag = '[object Array]',
+const arrayTag = '[object Array]';
-    boolTag = '[object Boolean]',
+const boolTag = '[object Boolean]';
-    dateTag = '[object Date]',
+const dateTag = '[object Date]';
-    errorTag = '[object Error]',
+const errorTag = '[object Error]';
-    funcTag = '[object Function]',
+const funcTag = '[object Function]';
-    genTag = '[object GeneratorFunction]',
+const genTag = '[object GeneratorFunction]';
-    mapTag = '[object Map]',
+const mapTag = '[object Map]';
-    numberTag = '[object Number]',
+const numberTag = '[object Number]';
-    objectTag = '[object Object]',
+const objectTag = '[object Object]';
-    regexpTag = '[object RegExp]',
+const regexpTag = '[object RegExp]';
-    setTag = '[object Set]',
+const setTag = '[object Set]';
-    stringTag = '[object String]',
+const stringTag = '[object String]';
-    symbolTag = '[object Symbol]',
+const symbolTag = '[object Symbol]';
-    weakMapTag = '[object WeakMap]';
+const weakMapTag = '[object WeakMap]';
 
-var arrayBufferTag = '[object ArrayBuffer]',
+const arrayBufferTag = '[object ArrayBuffer]';
-    dataViewTag = '[object DataView]',
+const dataViewTag = '[object DataView]';
-    float32Tag = '[object Float32Array]',
+const float32Tag = '[object Float32Array]';
-    float64Tag = '[object Float64Array]',
+const float64Tag = '[object Float64Array]';
-    int8Tag = '[object Int8Array]',
+const int8Tag = '[object Int8Array]';
-    int16Tag = '[object Int16Array]',
+const int16Tag = '[object Int16Array]';
-    int32Tag = '[object Int32Array]',
+const int32Tag = '[object Int32Array]';
-    uint8Tag = '[object Uint8Array]',
+const uint8Tag = '[object Uint8Array]';
-    uint8ClampedTag = '[object Uint8ClampedArray]',
+const uint8ClampedTag = '[object Uint8ClampedArray]';
-    uint16Tag = '[object Uint16Array]',
+const uint16Tag = '[object Uint16Array]';
-    uint32Tag = '[object Uint32Array]';
+const uint32Tag = '[object Uint32Array]';
 
 /** Used to identify `toStringTag` values supported by `_.clone`. */
-var cloneableTags = {};
+const cloneableTags = {};
 cloneableTags[argsTag] = cloneableTags[arrayTag] =
 cloneableTags[arrayBufferTag] = cloneableTags[dataViewTag] =
 cloneableTags[boolTag] = cloneableTags[dateTag] =
@@ -85,10 +85,10 @@ cloneableTags[weakMapTag] = false;
  * @returns {*} Returns the cloned value.
  */
 function baseClone(value, bitmask, customizer, key, object, stack) {
-  var result,
+  let result;
-      isDeep = bitmask & CLONE_DEEP_FLAG,
+  const isDeep = bitmask & CLONE_DEEP_FLAG;
-      isFlat = bitmask & CLONE_FLAT_FLAG,
+  const isFlat = bitmask & CLONE_FLAT_FLAG;
-      isFull = bitmask & CLONE_SYMBOLS_FLAG;
+  const isFull = bitmask & CLONE_SYMBOLS_FLAG;
 
   if (customizer) {
     result = object ? customizer(value, key, object, stack) : customizer(value);
@@ -99,15 +99,15 @@ function baseClone(value, bitmask, customizer, key, object, stack) {
   if (!isObject(value)) {
     return value;
   }
-  var isArr = isArray(value);
+  const isArr = isArray(value);
   if (isArr) {
     result = initCloneArray(value);
     if (!isDeep) {
       return copyArray(value, result);
     }
   } else {
-    var tag = getTag(value),
+    const tag = getTag(value);
-        isFunc = tag == funcTag || tag == genTag;
+    const isFunc = tag == funcTag || tag == genTag;
 
     if (isBuffer(value)) {
       return cloneBuffer(value, isDeep);
@@ -128,17 +128,17 @@ function baseClone(value, bitmask, customizer, key, object, stack) {
   }
   // Check for circular references and return its corresponding clone.
   stack || (stack = new Stack);
-  var stacked = stack.get(value);
+  const stacked = stack.get(value);
   if (stacked) {
     return stacked;
   }
   stack.set(value, result);
 
-  var keysFunc = isFull
+  const keysFunc = isFull
     ? (isFlat ? getAllKeysIn : getAllKeys)
     : (isFlat ? keysIn : keys);
 
-  var props = isArr ? undefined : keysFunc(value);
+  const props = isArr ? undefined : keysFunc(value);
   arrayEach(props || value, (subValue, key) => {
     if (props) {
       key = subValue;

_baseDifference.js

@@ -6,7 +6,7 @@ import baseUnary from './_baseUnary.js';
 import cacheHas from './_cacheHas.js';
 
 /** Used as the size to enable large array optimizations. */
-var LARGE_ARRAY_SIZE = 200;
+const LARGE_ARRAY_SIZE = 200;
 
 /**
  * The base implementation of methods like `_.difference` without support
@@ -20,12 +20,12 @@ var LARGE_ARRAY_SIZE = 200;
  * @returns {Array} Returns the new array of filtered values.
  */
 function baseDifference(array, values, iteratee, comparator) {
-  var index = -1,
+  let index = -1;
-      includes = arrayIncludes,
+  let includes = arrayIncludes;
-      isCommon = true,
+  let isCommon = true;
-      length = array.length,
+  const length = array.length;
-      result = [],
+  const result = [];
-      valuesLength = values.length;
+  const valuesLength = values.length;
 
   if (!length) {
     return result;
@@ -44,12 +44,12 @@ function baseDifference(array, values, iteratee, comparator) {
   }
   outer:
   while (++index < length) {
-    var value = array[index],
+    let value = array[index];
-        computed = iteratee == null ? value : iteratee(value);
+    const computed = iteratee == null ? value : iteratee(value);
 
     value = (comparator || value !== 0) ? value : 0;
     if (isCommon && computed === computed) {
-      var valuesIndex = valuesLength;
+      let valuesIndex = valuesLength;
       while (valuesIndex--) {
         if (values[valuesIndex] === computed) {
           continue outer;

_baseIntersection.js

@@ -6,7 +6,7 @@ import baseUnary from './_baseUnary.js';
 import cacheHas from './_cacheHas.js';
 
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeMin = Math.min;
+const nativeMin = Math.min;
 
 /**
  * The base implementation of methods like `_.intersection`, without support
@@ -19,13 +19,14 @@ var nativeMin = Math.min;
  * @returns {Array} Returns the new array of shared values.
  */
 function baseIntersection(arrays, iteratee, comparator) {
-  var includes = comparator ? arrayIncludesWith : arrayIncludes,
+  const includes = comparator ? arrayIncludesWith : arrayIncludes;
-      length = arrays[0].length,
+  const length = arrays[0].length;
-      othLength = arrays.length,
+  const othLength = arrays.length;
-      othIndex = othLength,
+  const caches = Array(othLength);
-      caches = Array(othLength),
+  const result = [];
-      maxLength = Infinity,
+
-      result = [];
+  let maxLength = Infinity;
+  let othIndex = othLength;
 
   while (othIndex--) {
     var array = arrays[othIndex];
@@ -39,13 +40,13 @@ function baseIntersection(arrays, iteratee, comparator) {
   }
   array = arrays[0];
 
-  var index = -1,
+  let index = -1;
-      seen = caches[0];
+  const seen = caches[0];
 
   outer:
   while (++index < length && result.length < maxLength) {
-    var value = array[index],
+    let value = array[index];
-        computed = iteratee ? iteratee(value) : value;
+    const computed = iteratee ? iteratee(value) : value;
 
     value = (comparator || value !== 0) ? value : 0;
     if (!(seen
@@ -54,7 +55,7 @@ function baseIntersection(arrays, iteratee, comparator) {
         )) {
       othIndex = othLength;
       while (--othIndex) {
-        var cache = caches[othIndex];
+        const cache = caches[othIndex];
         if (!(cache
               ? cacheHas(cache, computed)
               : includes(arrays[othIndex], computed, comparator))

_baseIsEqualDeep.js

@@ -8,18 +8,18 @@ import isBuffer from './isBuffer.js';
 import isTypedArray from './isTypedArray.js';
 
 /** Used to compose bitmasks for value comparisons. */
-var COMPARE_PARTIAL_FLAG = 1;
+const COMPARE_PARTIAL_FLAG = 1;
 
 /** `Object#toString` result references. */
-var argsTag = '[object Arguments]',
+const argsTag = '[object Arguments]';
-    arrayTag = '[object Array]',
+const arrayTag = '[object Array]';
-    objectTag = '[object Object]';
+const objectTag = '[object Object]';
 
 /** Used for built-in method references. */
-var objectProto = Object.prototype;
+const objectProto = Object.prototype;
 
 /** Used to check objects for own properties. */
-var hasOwnProperty = objectProto.hasOwnProperty;
+const hasOwnProperty = objectProto.hasOwnProperty;
 
 /**
  * A specialized version of `baseIsEqual` for arrays and objects which performs
@@ -36,17 +36,17 @@ var hasOwnProperty = objectProto.hasOwnProperty;
  * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
  */
 function baseIsEqualDeep(object, other, bitmask, customizer, equalFunc, stack) {
-  var objIsArr = isArray(object),
+  let objIsArr = isArray(object);
-      othIsArr = isArray(other),
+  const othIsArr = isArray(other);
-      objTag = objIsArr ? arrayTag : getTag(object),
+  let objTag = objIsArr ? arrayTag : getTag(object);
-      othTag = othIsArr ? arrayTag : getTag(other);
+  let othTag = othIsArr ? arrayTag : getTag(other);
 
   objTag = objTag == argsTag ? objectTag : objTag;
   othTag = othTag == argsTag ? objectTag : othTag;
 
-  var objIsObj = objTag == objectTag,
+  let objIsObj = objTag == objectTag;
-      othIsObj = othTag == objectTag,
+  const othIsObj = othTag == objectTag;
-      isSameTag = objTag == othTag;
+  const isSameTag = objTag == othTag;
 
   if (isSameTag && isBuffer(object)) {
     if (!isBuffer(other)) {
@@ -62,12 +62,12 @@ function baseIsEqualDeep(object, other, bitmask, customizer, equalFunc, stack) {
       : equalByTag(object, other, objTag, bitmask, customizer, equalFunc, stack);
   }
   if (!(bitmask & COMPARE_PARTIAL_FLAG)) {
-    var objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'),
+    const objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__');
-        othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__');
+    const othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__');
 
     if (objIsWrapped || othIsWrapped) {
-      var objUnwrapped = objIsWrapped ? object.value() : object,
+      const objUnwrapped = objIsWrapped ? object.value() : object;
-          othUnwrapped = othIsWrapped ? other.value() : other;
+      const othUnwrapped = othIsWrapped ? other.value() : other;
 
       stack || (stack = new Stack);
       return equalFunc(objUnwrapped, othUnwrapped, bitmask, customizer, stack);

_baseIsMatch.js

@@ -2,8 +2,8 @@ import Stack from './_Stack.js';
 import baseIsEqual from './_baseIsEqual.js';
 
 /** Used to compose bitmasks for value comparisons. */
-var COMPARE_PARTIAL_FLAG = 1,
+const COMPARE_PARTIAL_FLAG = 1;
-    COMPARE_UNORDERED_FLAG = 2;
+const COMPARE_UNORDERED_FLAG = 2;
 
 /**
  * The base implementation of `_.isMatch` without support for iteratee shorthands.
@@ -16,16 +16,18 @@ var COMPARE_PARTIAL_FLAG = 1,
  * @returns {boolean} Returns `true` if `object` is a match, else `false`.
  */
 function baseIsMatch(object, source, matchData, customizer) {
-  var index = matchData.length,
+  let index = matchData.length;
-      length = index,
+  const length = index;
-      noCustomizer = !customizer;
+  const noCustomizer = !customizer;
 
   if (object == null) {
     return !length;
   }
+  let data;
+  let result;
   object = Object(object);
   while (index--) {
-    var data = matchData[index];
+    data = matchData[index];
     if ((noCustomizer && data[2])
           ? data[1] !== object[data[0]]
           : !(data[0] in object)
@@ -35,18 +37,18 @@ function baseIsMatch(object, source, matchData, customizer) {
   }
   while (++index < length) {
     data = matchData[index];
-    var key = data[0],
+    const key = data[0];
-        objValue = object[key],
+    const objValue = object[key];
-        srcValue = data[1];
+    const srcValue = data[1];
 
     if (noCustomizer && data[2]) {
       if (objValue === undefined && !(key in object)) {
         return false;
       }
     } else {
-      var stack = new Stack;
+      const stack = new Stack;
       if (customizer) {
-        var result = customizer(objValue, srcValue, key, object, source, stack);
+        result = customizer(objValue, srcValue, key, object, source, stack);
       }
       if (!(result === undefined
             ? baseIsEqual(srcValue, objValue, COMPARE_PARTIAL_FLAG | COMPARE_UNORDERED_FLAG, customizer, stack)

_baseIsTypedArray.js

@@ -3,34 +3,34 @@ import isLength from './isLength.js';
 import isObjectLike from './isObjectLike.js';
 
 /** `Object#toString` result references. */
-var argsTag = '[object Arguments]',
+const argsTag = '[object Arguments]';
-    arrayTag = '[object Array]',
+const arrayTag = '[object Array]';
-    boolTag = '[object Boolean]',
+const boolTag = '[object Boolean]';
-    dateTag = '[object Date]',
+const dateTag = '[object Date]';
-    errorTag = '[object Error]',
+const errorTag = '[object Error]';
-    funcTag = '[object Function]',
+const funcTag = '[object Function]';
-    mapTag = '[object Map]',
+const mapTag = '[object Map]';
-    numberTag = '[object Number]',
+const numberTag = '[object Number]';
-    objectTag = '[object Object]',
+const objectTag = '[object Object]';
-    regexpTag = '[object RegExp]',
+const regexpTag = '[object RegExp]';
-    setTag = '[object Set]',
+const setTag = '[object Set]';
-    stringTag = '[object String]',
+const stringTag = '[object String]';
-    weakMapTag = '[object WeakMap]';
+const weakMapTag = '[object WeakMap]';
 
-var arrayBufferTag = '[object ArrayBuffer]',
+const arrayBufferTag = '[object ArrayBuffer]';
-    dataViewTag = '[object DataView]',
+const dataViewTag = '[object DataView]';
-    float32Tag = '[object Float32Array]',
+const float32Tag = '[object Float32Array]';
-    float64Tag = '[object Float64Array]',
+const float64Tag = '[object Float64Array]';
-    int8Tag = '[object Int8Array]',
+const int8Tag = '[object Int8Array]';
-    int16Tag = '[object Int16Array]',
+const int16Tag = '[object Int16Array]';
-    int32Tag = '[object Int32Array]',
+const int32Tag = '[object Int32Array]';
-    uint8Tag = '[object Uint8Array]',
+const uint8Tag = '[object Uint8Array]';
-    uint8ClampedTag = '[object Uint8ClampedArray]',
+const uint8ClampedTag = '[object Uint8ClampedArray]';
-    uint16Tag = '[object Uint16Array]',
+const uint16Tag = '[object Uint16Array]';
-    uint32Tag = '[object Uint32Array]';
+const uint32Tag = '[object Uint32Array]';
 
 /** Used to identify `toStringTag` values of typed arrays. */
-var typedArrayTags = {};
+const typedArrayTags = {};
 typedArrayTags[float32Tag] = typedArrayTags[float64Tag] =
 typedArrayTags[int8Tag] = typedArrayTags[int16Tag] =
 typedArrayTags[int32Tag] = typedArrayTags[uint8Tag] =

_baseMergeDeep.js

@@ -29,24 +29,24 @@ import toPlainObject from './toPlainObject.js';
  *  counterparts.
  */
 function baseMergeDeep(object, source, key, srcIndex, mergeFunc, customizer, stack) {
-  var objValue = object[key],
+  const objValue = object[key];
-      srcValue = source[key],
+  const srcValue = source[key];
-      stacked = stack.get(srcValue);
+  const stacked = stack.get(srcValue);
 
   if (stacked) {
     assignMergeValue(object, key, stacked);
     return;
   }
-  var newValue = customizer
+  let newValue = customizer
     ? customizer(objValue, srcValue, `${ key }`, object, source, stack)
     : undefined;
 
-  var isCommon = newValue === undefined;
+  let isCommon = newValue === undefined;
 
   if (isCommon) {
-    var isArr = isArray(srcValue),
+    const isArr = isArray(srcValue);
-        isBuff = !isArr && isBuffer(srcValue),
+    const isBuff = !isArr && isBuffer(srcValue);
-        isTyped = !isArr && !isBuff && isTypedArray(srcValue);
+    const isTyped = !isArr && !isBuff && isTypedArray(srcValue);
 
     newValue = srcValue;
     if (isArr || isBuff || isTyped) {

_basePickBy.js

@@ -12,14 +12,13 @@ import castPath from './_castPath.js';
  * @returns {Object} Returns the new object.
  */
 function basePickBy(object, paths, predicate) {
-  var index = -1,
+  let index = -1;
-      length = paths.length,
+  const length = paths.length;
-      result = {};
+  const result = {};
 
   while (++index < length) {
-    var path = paths[index],
+    const path = paths[index];
-        value = baseGet(object, path);
+    const value = baseGet(object, path);
-
     if (predicate(value, path)) {
       baseSet(result, castPath(path, object), value);
     }

_basePullAll.js

@@ -5,10 +5,10 @@ import baseUnary from './_baseUnary.js';
 import copyArray from './_copyArray.js';
 
 /** Used for built-in method references. */
-var arrayProto = Array.prototype;
+const arrayProto = Array.prototype;
 
 /** Built-in value references. */
-var splice = arrayProto.splice;
+const splice = arrayProto.splice;
 
 /**
  * The base implementation of `_.pullAllBy` without support for iteratee
@@ -22,10 +22,11 @@ var splice = arrayProto.splice;
  * @returns {Array} Returns `array`.
  */
 function basePullAll(array, values, iteratee, comparator) {
-  var indexOf = comparator ? baseIndexOfWith : baseIndexOf,
+  const indexOf = comparator ? baseIndexOfWith : baseIndexOf;
-      index = -1,
+  const length = values.length;
-      length = values.length,
+
-      seen = array;
+  let index = -1;
+  let seen = array;
 
   if (array === values) {
     values = copyArray(values);
@@ -34,9 +35,9 @@ function basePullAll(array, values, iteratee, comparator) {
     seen = arrayMap(array, baseUnary(iteratee));
   }
   while (++index < length) {
-    var fromIndex = 0,
+    let fromIndex = 0;
-        value = values[index],
+    const value = values[index];
-        computed = iteratee ? iteratee(value) : value;
+    const computed = iteratee ? iteratee(value) : value;
 
     while ((fromIndex = indexOf(seen, computed, fromIndex, comparator)) > -1) {
       if (seen !== array) {

_baseRandom.js

@@ -1,6 +1,6 @@
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeFloor = Math.floor,
+const nativeFloor = Math.floor;
-    nativeRandom = Math.random;
+const nativeRandom = Math.random;
 
 /**
  * The base implementation of `_.random` without support for returning

_baseRange.js

@@ -1,6 +1,6 @@
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeCeil = Math.ceil,
+const nativeCeil = Math.ceil;
-    nativeMax = Math.max;
+const nativeMax = Math.max;
 
 /**
  * The base implementation of `_.range` and `_.rangeRight` which doesn't
@@ -14,9 +14,9 @@ var nativeCeil = Math.ceil,
  * @returns {Array} Returns the range of numbers.
  */
 function baseRange(start, end, step, fromRight) {
-  var index = -1,
+  let index = -1;
-      length = nativeMax(nativeCeil((end - start) / (step || 1)), 0),
+  let length = nativeMax(nativeCeil((end - start) / (step || 1)), 0);
-      result = Array(length);
+  const result = Array(length);
 
   while (length--) {
     result[fromRight ? length : ++index] = start;

_baseSet.js

@@ -20,17 +20,18 @@ function baseSet(object, path, value, customizer) {
   }
   path = castPath(path, object);
 
-  var index = -1,
+  const length = path.length;
-      length = path.length,
+  const lastIndex = length - 1;
-      lastIndex = length - 1,
+
-      nested = object;
+  let index = -1;
+  let nested = object;
 
   while (nested != null && ++index < length) {
-    var key = toKey(path[index]),
+    const key = toKey(path[index]);
-        newValue = value;
+    let newValue = value;
 
     if (index != lastIndex) {
-      var objValue = nested[key];
+      const objValue = nested[key];
       newValue = customizer ? customizer(objValue, key, nested) : undefined;
       if (newValue === undefined) {
         newValue = isObject(objValue)

_baseSlice.js

@@ -8,7 +8,7 @@
  * @returns {Array} Returns the slice of `array`.
  */
 function baseSlice(array, start, end) {
-  var index = -1,
+  let index = -1,
       length = array.length;
 
   if (start < 0) {
@@ -21,7 +21,7 @@ function baseSlice(array, start, end) {
   length = start > end ? 0 : ((end - start) >>> 0);
   start >>>= 0;
 
-  var result = Array(length);
+  const result = Array(length);
   while (++index < length) {
     result[index] = array[index + start];
   }

_baseSortedIndex.js

@@ -3,8 +3,8 @@ import identity from './identity.js';
 import isSymbol from './isSymbol.js';
 
 /** Used as references for the maximum length and index of an array. */
-var MAX_ARRAY_LENGTH = 4294967295,
+const MAX_ARRAY_LENGTH = 4294967295;
-    HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1;
+const HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1;
 
 /**
  * The base implementation of `_.sortedIndex` and `_.sortedLastIndex` which
@@ -19,14 +19,13 @@ var MAX_ARRAY_LENGTH = 4294967295,
  *  into `array`.
  */
 function baseSortedIndex(array, value, retHighest) {
-  var low = 0,
+  let low = 0;
-      high = array == null ? low : array.length;
+  let high = array == null ? low : array.length;
 
   if (typeof value == 'number' && value === value && high <= HALF_MAX_ARRAY_LENGTH) {
     while (low < high) {
-      var mid = (low + high) >>> 1,
+      const mid = (low + high) >>> 1;
-          computed = array[mid];
+      const computed = array[mid];
-
       if (computed !== null && !isSymbol(computed) &&
           (retHighest ? (computed <= value) : (computed < value))) {
         low = mid + 1;

_baseSortedIndexBy.js

@@ -1,12 +1,11 @@
 import isSymbol from './isSymbol.js';
 
 /** Used as references for the maximum length and index of an array. */
-var MAX_ARRAY_LENGTH = 4294967295,
+const MAX_ARRAY_LENGTH = 4294967295;
-    MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1;
+const MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1;
 
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeFloor = Math.floor,
+const nativeFloor = Math.floor, nativeMin = Math.min;
-    nativeMin = Math.min;
 
 /**
  * The base implementation of `_.sortedIndexBy` and `_.sortedLastIndexBy`
@@ -24,20 +23,20 @@ var nativeFloor = Math.floor,
 function baseSortedIndexBy(array, value, iteratee, retHighest) {
   value = iteratee(value);
 
-  var low = 0,
+  let low = 0;
-      high = array == null ? 0 : array.length,
+  let high = array == null ? 0 : array.length;
-      valIsNaN = value !== value,
+  const valIsNaN = value !== value;
-      valIsNull = value === null,
+  const valIsNull = value === null;
-      valIsSymbol = isSymbol(value),
+  const valIsSymbol = isSymbol(value);
-      valIsUndefined = value === undefined;
+  const valIsUndefined = value === undefined;
 
   while (low < high) {
-    var mid = nativeFloor((low + high) / 2),
+    const mid = nativeFloor((low + high) / 2);
-        computed = iteratee(array[mid]),
+    const computed = iteratee(array[mid]);
-        othIsDefined = computed !== undefined,
+    const othIsDefined = computed !== undefined;
-        othIsNull = computed === null,
+    const othIsNull = computed === null;
-        othIsReflexive = computed === computed,
+    const othIsReflexive = computed === computed;
-        othIsSymbol = isSymbol(computed);
+    const othIsSymbol = isSymbol(computed);
 
     if (valIsNaN) {
       var setLow = retHighest || othIsReflexive;

_baseSortedUniq.js

@@ -10,17 +10,17 @@ import eq from './eq.js';
  * @returns {Array} Returns the new duplicate free array.
  */
 function baseSortedUniq(array, iteratee) {
-  var index = -1,
+  let seen;
-      length = array.length,
+  let index = -1;
-      resIndex = 0,
+  let resIndex = 0;
-      result = [];
+
+  const length = array.length;
+  const result = [];
 
   while (++index < length) {
-    var value = array[index],
+    const value = array[index], computed = iteratee ? iteratee(value) : value;
-        computed = iteratee ? iteratee(value) : value;
-
     if (!index || !eq(computed, seen)) {
-      var seen = computed;
+      seen = computed;
       result[resIndex++] = value === 0 ? 0 : value;
     }
   }

_baseUniq.js

@@ -6,7 +6,7 @@ import createSet from './_createSet.js';
 import setToArray from './_setToArray.js';
 
 /** Used as the size to enable large array optimizations. */
-var LARGE_ARRAY_SIZE = 200;
+const LARGE_ARRAY_SIZE = 200;
 
 /**
  * The base implementation of `_.uniqBy` without support for iteratee shorthands.
@@ -18,19 +18,20 @@ var LARGE_ARRAY_SIZE = 200;
  * @returns {Array} Returns the new duplicate free array.
  */
 function baseUniq(array, iteratee, comparator) {
-  var index = -1,
+  let index = -1;
-      includes = arrayIncludes,
+  let includes = arrayIncludes;
-      length = array.length,
+  let isCommon = true;
-      isCommon = true,
+
-      result = [],
+  const length = array.length;
-      seen = result;
+  const result = [];
+  let seen = result;
 
   if (comparator) {
     isCommon = false;
     includes = arrayIncludesWith;
   }
   else if (length >= LARGE_ARRAY_SIZE) {
-    var set = iteratee ? null : createSet(array);
+    const set = iteratee ? null : createSet(array);
     if (set) {
       return setToArray(set);
     }
@@ -43,12 +44,12 @@ function baseUniq(array, iteratee, comparator) {
   }
   outer:
   while (++index < length) {
-    var value = array[index],
+    let value = array[index];
-        computed = iteratee ? iteratee(value) : value;
+    const computed = iteratee ? iteratee(value) : value;
 
     value = (comparator || value !== 0) ? value : 0;
     if (isCommon && computed === computed) {
-      var seenIndex = seen.length;
+      let seenIndex = seen.length;
       while (seenIndex--) {
         if (seen[seenIndex] === computed) {
           continue outer;

_cloneBuffer.js

@@ -1,17 +1,16 @@
 import root from './_root.js';
 
 /** Detect free variable `exports`. */
-var freeExports = typeof exports == 'object' && exports && !exports.nodeType && exports;
+const freeExports = typeof exports == 'object' && exports && !exports.nodeType && exports;
 
 /** Detect free variable `module`. */
-var freeModule = freeExports && typeof module == 'object' && module && !module.nodeType && module;
+const freeModule = freeExports && typeof module == 'object' && module && !module.nodeType && module;
 
 /** Detect the popular CommonJS extension `module.exports`. */
-var moduleExports = freeModule && freeModule.exports === freeExports;
+const moduleExports = freeModule && freeModule.exports === freeExports;
 
 /** Built-in value references. */
-var Buffer = moduleExports ? root.Buffer : undefined,
+const Buffer = moduleExports ? root.Buffer : undefined, allocUnsafe = Buffer ? Buffer.allocUnsafe : undefined;
-    allocUnsafe = Buffer ? Buffer.allocUnsafe : undefined;
 
 /**
  * Creates a clone of  `buffer`.
@@ -25,8 +24,8 @@ function cloneBuffer(buffer, isDeep) {
   if (isDeep) {
     return buffer.slice();
   }
-  var length = buffer.length,
+  const length = buffer.length;
-      result = allocUnsafe ? allocUnsafe(length) : new buffer.constructor(length);
+  const result = allocUnsafe ? allocUnsafe(length) : new buffer.constructor(length);
 
   buffer.copy(result);
   return result;

_cloneSymbol.js

@@ -1,8 +1,8 @@
 import Symbol from './_Symbol.js';
 
 /** Used to convert symbols to primitives and strings. */
-var symbolProto = Symbol ? Symbol.prototype : undefined,
+const symbolProto = Symbol ? Symbol.prototype : undefined;
-    symbolValueOf = symbolProto ? symbolProto.valueOf : undefined;
+const symbolValueOf = symbolProto ? symbolProto.valueOf : undefined;
 
 /**
  * Creates a clone of the `symbol` object.

_compareAscending.js

@@ -10,15 +10,15 @@ import isSymbol from './isSymbol.js';
  */
 function compareAscending(value, other) {
   if (value !== other) {
-    var valIsDefined = value !== undefined,
+    const valIsDefined = value !== undefined;
-        valIsNull = value === null,
+    const valIsNull = value === null;
-        valIsReflexive = value === value,
+    const valIsReflexive = value === value;
-        valIsSymbol = isSymbol(value);
+    const valIsSymbol = isSymbol(value);
 
-    var othIsDefined = other !== undefined,
+    const othIsDefined = other !== undefined;
-        othIsNull = other === null,
+    const othIsNull = other === null;
-        othIsReflexive = other === other,
+    const othIsReflexive = other === other;
-        othIsSymbol = isSymbol(other);
+    const othIsSymbol = isSymbol(other);
 
     if ((!othIsNull && !othIsSymbol && !valIsSymbol && value > other) ||
         (valIsSymbol && othIsDefined && othIsReflexive && !othIsNull && !othIsSymbol) ||

_compareMultiple.js

@@ -15,19 +15,19 @@ import compareAscending from './_compareAscending.js';
  * @returns {number} Returns the sort order indicator for `object`.
  */
 function compareMultiple(object, other, orders) {
-  var index = -1,
+  let index = -1;
-      objCriteria = object.criteria,
+  const objCriteria = object.criteria;
-      othCriteria = other.criteria,
+  const othCriteria = other.criteria;
-      length = objCriteria.length,
+  const length = objCriteria.length;
-      ordersLength = orders.length;
+  const ordersLength = orders.length;
 
   while (++index < length) {
-    var result = compareAscending(objCriteria[index], othCriteria[index]);
+    const result = compareAscending(objCriteria[index], othCriteria[index]);
     if (result) {
       if (index >= ordersLength) {
         return result;
       }
-      var order = orders[index];
+      const order = orders[index];
       return result * (order == 'desc' ? -1 : 1);
     }
   }

_composeArgs.js

@@ -1,5 +1,5 @@
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeMax = Math.max;
+const nativeMax = Math.max;
 
 /**
  * Creates an array that is the composition of partially applied arguments,
@@ -13,14 +13,16 @@ var nativeMax = Math.max;
  * @returns {Array} Returns the new array of composed arguments.
  */
 function composeArgs(args, partials, holders, isCurried) {
-  var argsIndex = -1,
+  const argsLength = args.length;
-      argsLength = args.length,
+  const holdersLength = holders.length;
-      holdersLength = holders.length,
+  const leftLength = partials.length;
-      leftIndex = -1,
+
-      leftLength = partials.length,
+  let argsIndex = -1;
-      rangeLength = nativeMax(argsLength - holdersLength, 0),
+  let leftIndex = -1;
-      result = Array(leftLength + rangeLength),
+  let rangeLength = nativeMax(argsLength - holdersLength, 0);
-      isUncurried = !isCurried;
+
+  const result = Array(leftLength + rangeLength);
+  const isUncurried = !isCurried;
 
   while (++leftIndex < leftLength) {
     result[leftIndex] = partials[leftIndex];

_composeArgsRight.js

@@ -1,5 +1,5 @@
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeMax = Math.max;
+const nativeMax = Math.max;
 
 /**
  * This function is like `composeArgs` except that the arguments composition
@@ -13,20 +13,21 @@ var nativeMax = Math.max;
  * @returns {Array} Returns the new array of composed arguments.
  */
 function composeArgsRight(args, partials, holders, isCurried) {
-  var argsIndex = -1,
+  let argsIndex = -1;
-      argsLength = args.length,
+  let holdersIndex = -1;
-      holdersIndex = -1,
+  let rightIndex = -1;
-      holdersLength = holders.length,
+
-      rightIndex = -1,
+  const argsLength = args.length;
-      rightLength = partials.length,
+  const holdersLength = holders.length;
-      rangeLength = nativeMax(argsLength - holdersLength, 0),
+  const rightLength = partials.length;
-      result = Array(rangeLength + rightLength),
+  const rangeLength = nativeMax(argsLength - holdersLength, 0);
-      isUncurried = !isCurried;
+  const result = Array(rangeLength + rightLength);
+  const isUncurried = !isCurried;
 
   while (++argsIndex < rangeLength) {
     result[argsIndex] = args[argsIndex];
   }
-  var offset = argsIndex;
+  const offset = argsIndex;
   while (++rightIndex < rightLength) {
     result[offset + rightIndex] = partials[rightIndex];
   }

_countHolders.js

@@ -7,8 +7,8 @@
  * @returns {number} Returns the placeholder count.
  */
 function countHolders(array, placeholder) {
-  var length = array.length,
+  let length = array.length;
-      result = 0;
+  let result = 0;
 
   while (length--) {
     if (array[length] === placeholder) {

_createAggregator.js

@@ -13,9 +13,8 @@ import isArray from './isArray.js';
  */
 function createAggregator(setter, initializer) {
   return (collection, iteratee) => {
-    var func = isArray(collection) ? arrayAggregator : baseAggregator,
+    const func = isArray(collection) ? arrayAggregator : baseAggregator;
-        accumulator = initializer ? initializer() : {};
+    const accumulator = initializer ? initializer() : {};
-
     return func(collection, setter, baseIteratee(iteratee, 2), accumulator);
   };
 }

_createAssigner.js

@@ -10,10 +10,10 @@ import isIterateeCall from './_isIterateeCall.js';
  */
 function createAssigner(assigner) {
   return baseRest((object, sources) => {
-    var index = -1,
+    let index = -1;
-        length = sources.length,
+    let length = sources.length;
-        customizer = length > 1 ? sources[length - 1] : undefined,
+    let customizer = length > 1 ? sources[length - 1] : undefined;
-        guard = length > 2 ? sources[2] : undefined;
+    const guard = length > 2 ? sources[2] : undefined;
 
     customizer = (assigner.length > 3 && typeof customizer == 'function')
       ? (length--, customizer)
@@ -25,7 +25,7 @@ function createAssigner(assigner) {
     }
     object = Object(object);
     while (++index < length) {
-      var source = sources[index];
+      const source = sources[index];
       if (source) {
         assigner(object, source, index, customizer);
       }

_createBaseFor.js

@@ -7,13 +7,14 @@
  */
 function createBaseFor(fromRight) {
   return (object, iteratee, keysFunc) => {
-    var index = -1,
+    const iterable = Object(object);
-        iterable = Object(object),
+    const props = keysFunc(object);
-        props = keysFunc(object),
+
-        length = props.length;
+    let index = -1;
+    let length = props.length;
 
     while (length--) {
-      var key = props[fromRight ? length : ++index];
+      const key = props[fromRight ? length : ++index];
       if (iteratee(iterable[key], key, iterable) === false) {
         break;
       }

_createBind.js

@@ -2,7 +2,7 @@ import createCtor from './_createCtor.js';
 import root from './_root.js';
 
 /** Used to compose bitmasks for function metadata. */
-var WRAP_BIND_FLAG = 1;
+const WRAP_BIND_FLAG = 1;
 
 /**
  * Creates a function that wraps `func` to invoke it with the optional `this`
@@ -15,11 +15,11 @@ var WRAP_BIND_FLAG = 1;
  * @returns {Function} Returns the new wrapped function.
  */
 function createBind(func, bitmask, thisArg) {
-  var isBind = bitmask & WRAP_BIND_FLAG,
+  const isBind = bitmask & WRAP_BIND_FLAG;
-      Ctor = createCtor(func);
+  const Ctor = createCtor(func);
 
   function wrapper(...args) {
-    var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
+    const fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
     return fn.apply(isBind ? thisArg : this, args);
   }
   return wrapper;

_createCtor.js

@@ -14,7 +14,7 @@ function createCtor(Ctor) {
     // Use a `switch` statement to work with class constructors. See
     // http://ecma-international.org/ecma-262/7.0/#sec-ecmascript-function-objects-call-thisargument-argumentslist
     // for more details.
-    var args = arguments;
+    const args = arguments;
     switch (args.length) {
       case 0: return new Ctor;
       case 1: return new Ctor(args[0]);
@@ -25,8 +25,8 @@ function createCtor(Ctor) {
       case 6: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5]);
       case 7: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5], args[6]);
     }
-    var thisBinding = baseCreate(Ctor.prototype),
+    const thisBinding = baseCreate(Ctor.prototype);
-        result = Ctor.apply(thisBinding, args);
+    const result = Ctor.apply(thisBinding, args);
 
     // Mimic the constructor's `return` behavior.
     // See https://es5.github.io/#x13.2.2 for more details.

_createCurry.js

@@ -16,18 +16,19 @@ import root from './_root.js';
  * @returns {Function} Returns the new wrapped function.
  */
 function createCurry(func, bitmask, arity) {
-  var Ctor = createCtor(func);
+  const Ctor = createCtor(func);
 
   function wrapper() {
-    var length = arguments.length,
+    let length = arguments.length;
-        args = Array(length),
+    let index = length;
-        index = length,
+
-        placeholder = getHolder(wrapper);
+    const args = Array(length);
+    const placeholder = getHolder(wrapper);
 
     while (index--) {
       args[index] = arguments[index];
     }
-    var holders = (length < 3 && args[0] !== placeholder && args[length - 1] !== placeholder)
+    const holders = (length < 3 && args[0] !== placeholder && args[length - 1] !== placeholder)
       ? []
       : replaceHolders(args, placeholder);
 
@@ -37,7 +38,7 @@ function createCurry(func, bitmask, arity) {
         func, bitmask, createHybrid, wrapper.placeholder, undefined,
         args, holders, undefined, undefined, arity - length);
     }
-    var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
+    const fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
     return apply(fn, this, args);
   }
   return wrapper;

_createFlow.js

@@ -6,13 +6,13 @@ import isArray from './isArray.js';
 import isLaziable from './_isLaziable.js';
 
 /** Error message constants. */
-var FUNC_ERROR_TEXT = 'Expected a function';
+const FUNC_ERROR_TEXT = 'Expected a function';
 
 /** Used to compose bitmasks for function metadata. */
-var WRAP_CURRY_FLAG = 8,
+const WRAP_CURRY_FLAG = 8;
-    WRAP_PARTIAL_FLAG = 32,
+const WRAP_PARTIAL_FLAG = 32;
-    WRAP_ARY_FLAG = 128,
+const WRAP_ARY_FLAG = 128;
-    WRAP_REARG_FLAG = 256;
+const WRAP_REARG_FLAG = 256;
 
 /**
  * Creates a `_.flow` or `_.flowRight` function.
@@ -23,9 +23,9 @@ var WRAP_CURRY_FLAG = 8,
  */
 function createFlow(fromRight) {
   return flatRest(funcs => {
-    var length = funcs.length,
+    const length = funcs.length;
-        index = length,
+    const prereq = LodashWrapper.prototype.thru;
-        prereq = LodashWrapper.prototype.thru;
+    let index = length;
 
     if (fromRight) {
       funcs.reverse();
@@ -43,12 +43,12 @@ function createFlow(fromRight) {
     while (++index < length) {
       func = funcs[index];
 
-      var funcName = getFuncName(func),
+      const funcName = getFuncName(func);
-          data = funcName == 'wrapper' ? getData(func) : undefined;
+      const data = funcName == 'wrapper' ? getData(func) : undefined;
 
       if (data && isLaziable(data[0]) &&
             data[1] == (WRAP_ARY_FLAG | WRAP_CURRY_FLAG | WRAP_PARTIAL_FLAG | WRAP_REARG_FLAG) &&
-            !data[4].length && data[9] == 1
+               !data[4].length && data[9] == 1
           ) {
         wrapper = wrapper[getFuncName(data[0])](...data[3]);
       } else {
@@ -58,14 +58,13 @@ function createFlow(fromRight) {
       }
     }
     return function() {
-      var args = arguments,
+      const args = arguments;
-          value = args[0];
+      const value = args[0];
 
       if (wrapper && args.length == 1 && isArray(value)) {
         return wrapper.plant(value).value();
       }
-      var index = 0,
+      let index = 0, result = length ? funcs[index].apply(this, args) : value;
-          result = length ? funcs[index].apply(this, args) : value;
 
       while (++index < length) {
         result = funcs[index].call(this, result);

_createHybrid.js

@@ -9,12 +9,12 @@ import replaceHolders from './_replaceHolders.js';
 import root from './_root.js';
 
 /** Used to compose bitmasks for function metadata. */
-var WRAP_BIND_FLAG = 1,
+const WRAP_BIND_FLAG = 1;
-    WRAP_BIND_KEY_FLAG = 2,
+const WRAP_BIND_KEY_FLAG = 2;
-    WRAP_CURRY_FLAG = 8,
+const WRAP_CURRY_FLAG = 8;
-    WRAP_CURRY_RIGHT_FLAG = 16,
+const WRAP_CURRY_RIGHT_FLAG = 16;
-    WRAP_ARY_FLAG = 128,
+const WRAP_ARY_FLAG = 128;
-    WRAP_FLIP_FLAG = 512;
+const WRAP_FLIP_FLAG = 512;
 
 /**
  * Creates a function that wraps `func` to invoke it with optional `this`
@@ -36,24 +36,26 @@ var WRAP_BIND_FLAG = 1,
  * @returns {Function} Returns the new wrapped function.
  */
 function createHybrid(func, bitmask, thisArg, partials, holders, partialsRight, holdersRight, argPos, ary, arity) {
-  var isAry = bitmask & WRAP_ARY_FLAG,
+  const isAry = bitmask & WRAP_ARY_FLAG;
-      isBind = bitmask & WRAP_BIND_FLAG,
+  const isBind = bitmask & WRAP_BIND_FLAG;
-      isBindKey = bitmask & WRAP_BIND_KEY_FLAG,
+  const isBindKey = bitmask & WRAP_BIND_KEY_FLAG;
-      isCurried = bitmask & (WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG),
+  const isCurried = bitmask & (WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG);
-      isFlip = bitmask & WRAP_FLIP_FLAG,
+  const isFlip = bitmask & WRAP_FLIP_FLAG;
-      Ctor = isBindKey ? undefined : createCtor(func);
+  const Ctor = isBindKey ? undefined : createCtor(func);
 
   function wrapper() {
-    var length = arguments.length,
+    let holderCount;
-        args = Array(length),
+    let placeholder;
-        index = length;
+    let length = arguments.length;
+    let args = Array(length);
+    let index = length;
 
     while (index--) {
       args[index] = arguments[index];
     }
     if (isCurried) {
-      var placeholder = getHolder(wrapper),
+      placeholder = getHolder(wrapper);
-          holdersCount = countHolders(args, placeholder);
+      holdersCount = countHolders(args, placeholder);
     }
     if (partials) {
       args = composeArgs(args, partials, holders, isCurried);
@@ -63,14 +65,14 @@ function createHybrid(func, bitmask, thisArg, partials, holders, partialsRight,
     }
     length -= holdersCount;
     if (isCurried && length < arity) {
-      var newHolders = replaceHolders(args, placeholder);
+      const newHolders = replaceHolders(args, placeholder);
       return createRecurry(
         func, bitmask, createHybrid, wrapper.placeholder, thisArg,
         args, newHolders, argPos, ary, arity - length
       );
     }
-    var thisBinding = isBind ? thisArg : this,
+    const thisBinding = isBind ? thisArg : this;
-        fn = isBindKey ? thisBinding[func] : func;
+    let fn = isBindKey ? thisBinding[func] : func;
 
     length = args.length;
     if (argPos) {

_createPartial.js

@@ -3,7 +3,7 @@ import createCtor from './_createCtor.js';
 import root from './_root.js';
 
 /** Used to compose bitmasks for function metadata. */
-var WRAP_BIND_FLAG = 1;
+const WRAP_BIND_FLAG = 1;
 
 /**
  * Creates a function that wraps `func` to invoke it with the `this` binding
@@ -18,16 +18,17 @@ var WRAP_BIND_FLAG = 1;
  * @returns {Function} Returns the new wrapped function.
  */
 function createPartial(func, bitmask, thisArg, partials) {
-  var isBind = bitmask & WRAP_BIND_FLAG,
+  const isBind = bitmask & WRAP_BIND_FLAG;
-      Ctor = createCtor(func);
+  const Ctor = createCtor(func);
 
   function wrapper() {
-    var argsIndex = -1,
+    let argsIndex = -1;
-        argsLength = arguments.length,
+    let argsLength = arguments.length;
-        leftIndex = -1,
+    let leftIndex = -1;
-        leftLength = partials.length,
+
-        args = Array(leftLength + argsLength),
+    const leftLength = partials.length;
-        fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
+    const args = Array(leftLength + argsLength);
+    const fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
 
     while (++leftIndex < leftLength) {
       args[leftIndex] = partials[leftIndex];

_createRecurry.js

@@ -3,12 +3,12 @@ import setData from './_setData.js';
 import setWrapToString from './_setWrapToString.js';
 
 /** Used to compose bitmasks for function metadata. */
-var WRAP_BIND_FLAG = 1,
+const WRAP_BIND_FLAG = 1;
-    WRAP_BIND_KEY_FLAG = 2,
+const WRAP_BIND_KEY_FLAG = 2;
-    WRAP_CURRY_BOUND_FLAG = 4,
+const WRAP_CURRY_BOUND_FLAG = 4;
-    WRAP_CURRY_FLAG = 8,
+const WRAP_CURRY_FLAG = 8;
-    WRAP_PARTIAL_FLAG = 32,
+const WRAP_PARTIAL_FLAG = 32;
-    WRAP_PARTIAL_RIGHT_FLAG = 64;
+const WRAP_PARTIAL_RIGHT_FLAG = 64;
 
 /**
  * Creates a function that wraps `func` to continue currying.
@@ -28,11 +28,11 @@ var WRAP_BIND_FLAG = 1,
  * @returns {Function} Returns the new wrapped function.
  */
 function createRecurry(func, bitmask, wrapFunc, placeholder, thisArg, partials, holders, argPos, ary, arity) {
-  var isCurry = bitmask & WRAP_CURRY_FLAG,
+  const isCurry = bitmask & WRAP_CURRY_FLAG;
-      newHolders = isCurry ? holders : undefined,
+  const newHolders = isCurry ? holders : undefined;
-      newHoldersRight = isCurry ? undefined : holders,
+  const newHoldersRight = isCurry ? undefined : holders;
-      newPartials = isCurry ? partials : undefined,
+  const newPartials = isCurry ? partials : undefined;
-      newPartialsRight = isCurry ? undefined : partials;
+  const newPartialsRight = isCurry ? undefined : partials;
 
   bitmask |= (isCurry ? WRAP_PARTIAL_FLAG : WRAP_PARTIAL_RIGHT_FLAG);
   bitmask &= ~(isCurry ? WRAP_PARTIAL_RIGHT_FLAG : WRAP_PARTIAL_FLAG);
@@ -40,12 +40,12 @@ function createRecurry(func, bitmask, wrapFunc, placeholder, thisArg, partials,
   if (!(bitmask & WRAP_CURRY_BOUND_FLAG)) {
     bitmask &= ~(WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG);
   }
-  var newData = [
+  const newData = [
     func, bitmask, thisArg, newPartials, newHolders, newPartialsRight,
     newHoldersRight, argPos, ary, arity
   ];
 
-  var result = wrapFunc(...newData);
+  const result = wrapFunc(...newData);
   if (isLaziable(func)) {
     setData(result, newData);
   }

_createRound.js

@@ -3,7 +3,7 @@ import toNumber from './toNumber.js';
 import toString from './toString.js';
 
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeMin = Math.min;
+const nativeMin = Math.min;
 
 /**
  * Creates a function like `_.round`.
@@ -13,15 +13,15 @@ var nativeMin = Math.min;
  * @returns {Function} Returns the new round function.
  */
 function createRound(methodName) {
-  var func = Math[methodName];
+  const func = Math[methodName];
   return (number, precision) => {
     number = toNumber(number);
     precision = precision == null ? 0 : nativeMin(toInteger(precision), 292);
     if (precision) {
       // Shift with exponential notation to avoid floating-point issues.
       // See [MDN](https://mdn.io/round#Examples) for more details.
-      var pair = `${ toString(number) }e`.split('e'),
+      let pair = `${ toString(number) }e`.split('e');
-          value = func(`${ pair[0] }e${ +pair[1] + precision }`);
+      const value = func(`${ pair[0] }e${ +pair[1] + precision }`);
 
       pair = `${ toString(value) }e`.split('e');
       return +`${ pair[0] }e${ +pair[1] - precision }`;

_createToPairs.js

@@ -4,8 +4,8 @@ import mapToArray from './_mapToArray.js';
 import setToPairs from './_setToPairs.js';
 
 /** `Object#toString` result references. */
-var mapTag = '[object Map]',
+const mapTag = '[object Map]';
-    setTag = '[object Set]';
+const setTag = '[object Set]';
 
 /**
  * Creates a `_.toPairs` or `_.toPairsIn` function.
@@ -16,7 +16,7 @@ var mapTag = '[object Map]',
  */
 function createToPairs(keysFunc) {
   return object => {
-    var tag = getTag(object);
+    const tag = getTag(object);
     if (tag == mapTag) {
       return mapToArray(object);
     }

_createWrap.js

@@ -10,18 +10,18 @@ import setWrapToString from './_setWrapToString.js';
 import toInteger from './toInteger.js';
 
 /** Error message constants. */
-var FUNC_ERROR_TEXT = 'Expected a function';
+const FUNC_ERROR_TEXT = 'Expected a function';
 
 /** Used to compose bitmasks for function metadata. */
-var WRAP_BIND_FLAG = 1,
+const WRAP_BIND_FLAG = 1;
-    WRAP_BIND_KEY_FLAG = 2,
+const WRAP_BIND_KEY_FLAG = 2;
-    WRAP_CURRY_FLAG = 8,
+const WRAP_CURRY_FLAG = 8;
-    WRAP_CURRY_RIGHT_FLAG = 16,
+const WRAP_CURRY_RIGHT_FLAG = 16;
-    WRAP_PARTIAL_FLAG = 32,
+const WRAP_PARTIAL_FLAG = 32;
-    WRAP_PARTIAL_RIGHT_FLAG = 64;
+const WRAP_PARTIAL_RIGHT_FLAG = 64;
 
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeMax = Math.max;
+const nativeMax = Math.max;
 
 /**
  * Creates a function that either curries or invokes `func` with optional
@@ -49,11 +49,11 @@ var nativeMax = Math.max;
  * @returns {Function} Returns the new wrapped function.
  */
 function createWrap(func, bitmask, thisArg, partials, holders, argPos, ary, arity) {
-  var isBindKey = bitmask & WRAP_BIND_KEY_FLAG;
+  const isBindKey = bitmask & WRAP_BIND_KEY_FLAG;
   if (!isBindKey && typeof func != 'function') {
     throw new TypeError(FUNC_ERROR_TEXT);
   }
-  var length = partials ? partials.length : 0;
+  let length = partials ? partials.length : 0;
   if (!length) {
     bitmask &= ~(WRAP_PARTIAL_FLAG | WRAP_PARTIAL_RIGHT_FLAG);
     partials = holders = undefined;
@@ -68,9 +68,9 @@ function createWrap(func, bitmask, thisArg, partials, holders, argPos, ary, arit
 
     partials = holders = undefined;
   }
-  var data = isBindKey ? undefined : getData(func);
+  const data = isBindKey ? undefined : getData(func);
 
-  var newData = [
+  const newData = [
     func, bitmask, thisArg, partials, holders, partialsRight, holdersRight,
     argPos, ary, arity
   ];
@@ -99,7 +99,7 @@ function createWrap(func, bitmask, thisArg, partials, holders, argPos, ary, arit
   } else {
     result = createHybrid(...newData);
   }
-  var setter = data ? baseSetData : setData;
+  const setter = data ? baseSetData : setData;
   return setWrapToString(setter(result, newData), func, bitmask);
 }
 

_equalArrays.js

@@ -3,8 +3,8 @@ import arraySome from './_arraySome.js';
 import cacheHas from './_cacheHas.js';
 
 /** Used to compose bitmasks for value comparisons. */
-var COMPARE_PARTIAL_FLAG = 1,
+const COMPARE_PARTIAL_FLAG = 1;
-    COMPARE_UNORDERED_FLAG = 2;
+const COMPARE_UNORDERED_FLAG = 2;
 
 /**
  * A specialized version of `baseIsEqualDeep` for arrays with support for
@@ -20,29 +20,28 @@ var COMPARE_PARTIAL_FLAG = 1,
  * @returns {boolean} Returns `true` if the arrays are equivalent, else `false`.
  */
 function equalArrays(array, other, bitmask, customizer, equalFunc, stack) {
-  var isPartial = bitmask & COMPARE_PARTIAL_FLAG,
+  const isPartial = bitmask & COMPARE_PARTIAL_FLAG;
-      arrLength = array.length,
+  const arrLength = array.length;
-      othLength = other.length;
+  const othLength = other.length;
 
   if (arrLength != othLength && !(isPartial && othLength > arrLength)) {
     return false;
   }
   // Assume cyclic values are equal.
-  var stacked = stack.get(array);
+  const stacked = stack.get(array);
   if (stacked && stack.get(other)) {
     return stacked == other;
   }
-  var index = -1,
+  let index = -1;
-      result = true,
+  let result = true;
-      seen = (bitmask & COMPARE_UNORDERED_FLAG) ? new SetCache : undefined;
+  const seen = (bitmask & COMPARE_UNORDERED_FLAG) ? new SetCache : undefined;
 
   stack.set(array, other);
   stack.set(other, array);
 
   // Ignore non-index properties.
   while (++index < arrLength) {
-    var arrValue = array[index],
+    const arrValue = array[index], othValue = other[index];
-        othValue = other[index];
 
     if (customizer) {
       var compared = isPartial

_equalByTag.js

@@ -6,26 +6,26 @@ import mapToArray from './_mapToArray.js';
 import setToArray from './_setToArray.js';
 
 /** Used to compose bitmasks for value comparisons. */
-var COMPARE_PARTIAL_FLAG = 1,
+const COMPARE_PARTIAL_FLAG = 1;
-    COMPARE_UNORDERED_FLAG = 2;
+const COMPARE_UNORDERED_FLAG = 2;
 
 /** `Object#toString` result references. */
-var boolTag = '[object Boolean]',
+const boolTag = '[object Boolean]';
-    dateTag = '[object Date]',
+const dateTag = '[object Date]';
-    errorTag = '[object Error]',
+const errorTag = '[object Error]';
-    mapTag = '[object Map]',
+const mapTag = '[object Map]';
-    numberTag = '[object Number]',
+const numberTag = '[object Number]';
-    regexpTag = '[object RegExp]',
+const regexpTag = '[object RegExp]';
-    setTag = '[object Set]',
+const setTag = '[object Set]';
-    stringTag = '[object String]',
+const stringTag = '[object String]';
-    symbolTag = '[object Symbol]';
+const symbolTag = '[object Symbol]';
 
-var arrayBufferTag = '[object ArrayBuffer]',
+const arrayBufferTag = '[object ArrayBuffer]';
-    dataViewTag = '[object DataView]';
+const dataViewTag = '[object DataView]';
 
 /** Used to convert symbols to primitives and strings. */
-var symbolProto = Symbol ? Symbol.prototype : undefined,
+const symbolProto = Symbol ? Symbol.prototype : undefined;
-    symbolValueOf = symbolProto ? symbolProto.valueOf : undefined;
+const symbolValueOf = symbolProto ? symbolProto.valueOf : undefined;
 
 /**
  * A specialized version of `baseIsEqualDeep` for comparing objects of
@@ -79,17 +79,17 @@ function equalByTag(object, other, tag, bitmask, customizer, equalFunc, stack) {
       return object == `${ other }`;
 
     case mapTag:
-      var convert = mapToArray;
+      let convert = mapToArray;
 
     case setTag:
-      var isPartial = bitmask & COMPARE_PARTIAL_FLAG;
+      const isPartial = bitmask & COMPARE_PARTIAL_FLAG;
       convert || (convert = setToArray);
 
       if (object.size != other.size && !isPartial) {
         return false;
       }
       // Assume cyclic values are equal.
-      var stacked = stack.get(object);
+      const stacked = stack.get(object);
       if (stacked) {
         return stacked == other;
       }
@@ -97,7 +97,7 @@ function equalByTag(object, other, tag, bitmask, customizer, equalFunc, stack) {
 
       // Recursively compare objects (susceptible to call stack limits).
       stack.set(object, other);
-      var result = equalArrays(convert(object), convert(other), bitmask, customizer, equalFunc, stack);
+      const result = equalArrays(convert(object), convert(other), bitmask, customizer, equalFunc, stack);
       stack['delete'](object);
       return result;
 

_equalObjects.js

@@ -1,13 +1,13 @@
 import getAllKeys from './_getAllKeys.js';
 
 /** Used to compose bitmasks for value comparisons. */
-var COMPARE_PARTIAL_FLAG = 1;
+const COMPARE_PARTIAL_FLAG = 1;
 
 /** Used for built-in method references. */
-var objectProto = Object.prototype;
+const objectProto = Object.prototype;
 
 /** Used to check objects for own properties. */
-var hasOwnProperty = objectProto.hasOwnProperty;
+const hasOwnProperty = objectProto.hasOwnProperty;
 
 /**
  * A specialized version of `baseIsEqualDeep` for objects with support for
@@ -23,39 +23,41 @@ var hasOwnProperty = objectProto.hasOwnProperty;
  * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
  */
 function equalObjects(object, other, bitmask, customizer, equalFunc, stack) {
-  var isPartial = bitmask & COMPARE_PARTIAL_FLAG,
+  const isPartial = bitmask & COMPARE_PARTIAL_FLAG;
-      objProps = getAllKeys(object),
+  const objProps = getAllKeys(object);
-      objLength = objProps.length,
+  const objLength = objProps.length;
-      othProps = getAllKeys(other),
+  const othProps = getAllKeys(other);
-      othLength = othProps.length;
+  const othLength = othProps.length;
 
   if (objLength != othLength && !isPartial) {
     return false;
   }
-  var index = objLength;
+  let key;
+  let index = objLength;
   while (index--) {
-    var key = objProps[index];
+    key = objProps[index];
     if (!(isPartial ? key in other : hasOwnProperty.call(other, key))) {
       return false;
     }
   }
   // Assume cyclic values are equal.
-  var stacked = stack.get(object);
+  const stacked = stack.get(object);
   if (stacked && stack.get(other)) {
     return stacked == other;
   }
-  var result = true;
+  let result = true;
   stack.set(object, other);
   stack.set(other, object);
 
-  var skipCtor = isPartial;
+  let compared;
+  let skipCtor = isPartial;
   while (++index < objLength) {
     key = objProps[index];
-    var objValue = object[key],
+    const objValue = object[key];
-        othValue = other[key];
+    const othValue = other[key];
 
     if (customizer) {
-      var compared = isPartial
+      compared = isPartial
         ? customizer(othValue, objValue, key, other, object, stack)
         : customizer(objValue, othValue, key, object, other, stack);
     }
@@ -70,8 +72,8 @@ function equalObjects(object, other, bitmask, customizer, equalFunc, stack) {
     skipCtor || (skipCtor = key == 'constructor');
   }
   if (result && !skipCtor) {
-    var objCtor = object.constructor,
+    const objCtor = object.constructor;
-        othCtor = other.constructor;
+    const othCtor = other.constructor;
 
     // Non `Object` object instances with different constructors are not equal.
     if (objCtor != othCtor &&

_getFuncName.js

@@ -1,10 +1,10 @@
 import realNames from './_realNames.js';
 
 /** Used for built-in method references. */
-var objectProto = Object.prototype;
+const objectProto = Object.prototype;
 
 /** Used to check objects for own properties. */
-var hasOwnProperty = objectProto.hasOwnProperty;
+const hasOwnProperty = objectProto.hasOwnProperty;
 
 /**
  * Gets the name of `func`.
@@ -14,13 +14,13 @@ var hasOwnProperty = objectProto.hasOwnProperty;
  * @returns {string} Returns the function name.
  */
 function getFuncName(func) {
-  var result = `${ func.name }`,
+  const result = `${ func.name }`;
-      array = realNames[result],
+  const array = realNames[result];
-      length = hasOwnProperty.call(realNames, result) ? array.length : 0;
+  let length = hasOwnProperty.call(realNames, result) ? array.length : 0;
 
   while (length--) {
-    var data = array[length],
+    const data = array[length];
-        otherFunc = data.func;
+    const otherFunc = data.func;
     if (otherFunc == null || otherFunc == func) {
       return data.name;
     }

_getMatchData.js

@@ -9,13 +9,12 @@ import keys from './keys.js';
  * @returns {Array} Returns the match data of `object`.
  */
 function getMatchData(object) {
-  var result = keys(object),
+  const result = keys(object);
-      length = result.length;
+  let length = result.length;
 
   while (length--) {
-    var key = result[length],
+    const key = result[length];
-        value = object[key];
+    const value = object[key];
-
     result[length] = [key, value, isStrictComparable(value)];
   }
   return result;

_getRawTag.js

@@ -1,20 +1,20 @@
 import Symbol from './_Symbol.js';
 
 /** Used for built-in method references. */
-var objectProto = Object.prototype;
+const objectProto = Object.prototype;
 
 /** Used to check objects for own properties. */
-var hasOwnProperty = objectProto.hasOwnProperty;
+const hasOwnProperty = objectProto.hasOwnProperty;
 
 /**
  * Used to resolve the
  * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
  * of values.
  */
-var nativeObjectToString = objectProto.toString;
+const nativeObjectToString = objectProto.toString;
 
 /** Built-in value references. */
-var symToStringTag = Symbol ? Symbol.toStringTag : undefined;
+const symToStringTag = Symbol ? Symbol.toStringTag : undefined;
 
 /**
  * A specialized version of `baseGetTag` which ignores `Symbol.toStringTag` values.
@@ -24,15 +24,15 @@ var symToStringTag = Symbol ? Symbol.toStringTag : undefined;
  * @returns {string} Returns the raw `toStringTag`.
  */
 function getRawTag(value) {
-  var isOwn = hasOwnProperty.call(value, symToStringTag),
+  const isOwn = hasOwnProperty.call(value, symToStringTag);
-      tag = value[symToStringTag];
+  const tag = value[symToStringTag];
 
   try {
     value[symToStringTag] = undefined;
     var unmasked = true;
   } catch (e) {}
 
-  var result = nativeObjectToString.call(value);
+  const result = nativeObjectToString.call(value);
   if (unmasked) {
     if (isOwn) {
       value[symToStringTag] = tag;

_getTag.js

@@ -7,20 +7,19 @@ import baseGetTag from './_baseGetTag.js';
 import toSource from './_toSource.js';
 
 /** `Object#toString` result references. */
-var mapTag = '[object Map]',
+const dataViewTag = '[object DataView]';
-    objectTag = '[object Object]',
+const mapTag = '[object Map]';
-    promiseTag = '[object Promise]',
+const objectTag = '[object Object]';
-    setTag = '[object Set]',
+const promiseTag = '[object Promise]';
-    weakMapTag = '[object WeakMap]';
+const setTag = '[object Set]';
-
+const weakMapTag = '[object WeakMap]';
-var dataViewTag = '[object DataView]';
 
 /** Used to detect maps, sets, and weakmaps. */
-var dataViewCtorString = toSource(DataView),
+const dataViewCtorString = toSource(DataView);
-    mapCtorString = toSource(Map),
+const mapCtorString = toSource(Map);
-    promiseCtorString = toSource(Promise),
+const promiseCtorString = toSource(Promise);
-    setCtorString = toSource(Set),
+const setCtorString = toSource(Set);
-    weakMapCtorString = toSource(WeakMap);
+const weakMapCtorString = toSource(WeakMap);
 
 /**
  * Gets the `toStringTag` of `value`.
@@ -29,7 +28,7 @@ var dataViewCtorString = toSource(DataView),
  * @param {*} value The value to query.
  * @returns {string} Returns the `toStringTag`.
  */
-var getTag = baseGetTag;
+let getTag = baseGetTag;
 
 // Fallback for data views, maps, sets, and weak maps in IE 11 and promises in Node.js < 6.
 if ((DataView && getTag(new DataView(new ArrayBuffer(1))) != dataViewTag) ||
@@ -38,9 +37,9 @@ if ((DataView && getTag(new DataView(new ArrayBuffer(1))) != dataViewTag) ||
     (Set && getTag(new Set) != setTag) ||
     (WeakMap && getTag(new WeakMap) != weakMapTag)) {
   getTag = value => {
-    var result = baseGetTag(value),
+    const result = baseGetTag(value);
-        Ctor = result == objectTag ? value.constructor : undefined,
+    const Ctor = result == objectTag ? value.constructor : undefined;
-        ctorString = Ctor ? toSource(Ctor) : '';
+    const ctorString = Ctor ? toSource(Ctor) : '';
 
     if (ctorString) {
       switch (ctorString) {

_getView.js

@@ -1,6 +1,6 @@
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeMax = Math.max,
+const nativeMax = Math.max;
-    nativeMin = Math.min;
+const nativeMin = Math.min;
 
 /**
  * Gets the view, applying any `transforms` to the `start` and `end` positions.
@@ -13,12 +13,12 @@ var nativeMax = Math.max,
  *  positions of the view.
  */
 function getView(start, end, transforms) {
-  var index = -1,
+  let index = -1;
-      length = transforms.length;
+  const length = transforms.length;
 
   while (++index < length) {
-    var data = transforms[index],
+    const data = transforms[index];
-        size = data.size;
+    const size = data.size;
 
     switch (data.type) {
       case 'drop':      start += size; break;

_getWrapDetails.js

@@ -1,6 +1,6 @@
 /** Used to match wrap detail comments. */
-var reWrapDetails = /\{\n\/\* \[wrapped with (.+)\] \*/,
+const reWrapDetails = /\{\n\/\* \[wrapped with (.+)\] \*/;
-    reSplitDetails = /,? & /;
+const reSplitDetails = /,? & /;
 
 /**
  * Extracts wrapper details from the `source` body comment.
@@ -10,7 +10,7 @@ var reWrapDetails = /\{\n\/\* \[wrapped with (.+)\] \*/,
  * @returns {Array} Returns the wrapper details.
  */
 function getWrapDetails(source) {
-  var match = source.match(reWrapDetails);
+  const match = source.match(reWrapDetails);
   return match ? match[1].split(reSplitDetails) : [];
 }
 

_hasUnicodeWord.js

@@ -1,5 +1,5 @@
 /** Used to detect strings that need a more robust regexp to match words. */
-var reHasUnicodeWord = /[a-z][A-Z]|[A-Z]{2,}[a-z]|[0-9][a-zA-Z]|[a-zA-Z][0-9]|[^a-zA-Z0-9 ]/;
+const reHasUnicodeWord = /[a-z][A-Z]|[A-Z]{2,}[a-z]|[0-9][a-zA-Z]|[a-zA-Z][0-9]|[^a-zA-Z0-9 ]/;
 
 /**
  * Checks if `string` contains a word composed of Unicode symbols.

_initCloneArray.js

@@ -1,8 +1,8 @@
 /** Used for built-in method references. */
-var objectProto = Object.prototype;
+const objectProto = Object.prototype;
 
 /** Used to check objects for own properties. */
-var hasOwnProperty = objectProto.hasOwnProperty;
+const hasOwnProperty = objectProto.hasOwnProperty;
 
 /**
  * Initializes an array clone.
@@ -12,8 +12,8 @@ var hasOwnProperty = objectProto.hasOwnProperty;
  * @returns {Array} Returns the initialized clone.
  */
 function initCloneArray(array) {
-  var length = array.length,
+  const length = array.length;
-      result = array.constructor(length);
+  const result = array.constructor(length);
 
   // Add properties assigned by `RegExp#exec`.
   if (length && typeof array[0] == 'string' && hasOwnProperty.call(array, 'index')) {

_isFlattenable.js

@@ -3,7 +3,7 @@ import isArguments from './isArguments.js';
 import isArray from './isArray.js';
 
 /** Built-in value references. */
-var spreadableSymbol = Symbol ? Symbol.isConcatSpreadable : undefined;
+const spreadableSymbol = Symbol ? Symbol.isConcatSpreadable : undefined;
 
 /**
  * Checks if `value` is a flattenable `arguments` object or array.

_isIndex.js

@@ -1,8 +1,8 @@
 /** Used as references for various `Number` constants. */
-var MAX_SAFE_INTEGER = 9007199254740991;
+const MAX_SAFE_INTEGER = 9007199254740991;
 
 /** Used to detect unsigned integer values. */
-var reIsUint = /^(?:0|[1-9]\d*)$/;
+const reIsUint = /^(?:0|[1-9]\d*)$/;
 
 /**
  * Checks if `value` is a valid array-like index.

_isIterateeCall.js

@@ -17,7 +17,7 @@ function isIterateeCall(value, index, object) {
   if (!isObject(object)) {
     return false;
   }
-  var type = typeof index;
+  const type = typeof index;
   if (type == 'number'
         ? (isArrayLike(object) && isIndex(index, object.length))
         : (type == 'string' && index in object)

_isKey.js

@@ -2,8 +2,8 @@ import isArray from './isArray.js';
 import isSymbol from './isSymbol.js';
 
 /** Used to match property names within property paths. */
-var reIsDeepProp = /\.|\[(?:[^[\]]*|(["'])(?:(?!\1)[^\\]|\\.)*?\1)\]/,
+const reIsDeepProp = /\.|\[(?:[^[\]]*|(["'])(?:(?!\1)[^\\]|\\.)*?\1)\]/;
-    reIsPlainProp = /^\w*$/;
+const reIsPlainProp = /^\w*$/;
 
 /**
  * Checks if `value` is a property name and not a property path.
@@ -17,7 +17,7 @@ function isKey(value, object) {
   if (isArray(value)) {
     return false;
   }
-  var type = typeof value;
+  const type = typeof value;
   if (type == 'number' || type == 'symbol' || type == 'boolean' ||
       value == null || isSymbol(value)) {
     return true;

_isKeyable.js

@@ -6,7 +6,7 @@
  * @returns {boolean} Returns `true` if `value` is suitable, else `false`.
  */
 function isKeyable(value) {
-  var type = typeof value;
+  const type = typeof value;
   return (type == 'string' || type == 'number' || type == 'symbol' || type == 'boolean')
     ? (value !== '__proto__')
     : (value === null);

_isMaskable.js

@@ -9,6 +9,6 @@ import stubFalse from './stubFalse.js';
  * @param {*} value The value to check.
  * @returns {boolean} Returns `true` if `func` is maskable, else `false`.
  */
-var isMaskable = coreJsData ? isFunction : stubFalse;
+const isMaskable = coreJsData ? isFunction : stubFalse;
 
 export default isMaskable;

_isMasked.js

@@ -1,7 +1,7 @@
 import coreJsData from './_coreJsData.js';
 
 /** Used to detect methods masquerading as native. */
-var maskSrcKey = ((() => {
+const maskSrcKey = ((() => {
   const uid = /[^.]+$/.exec(coreJsData && coreJsData.keys && coreJsData.keys.IE_PROTO || '');
   return uid ? `Symbol(src)_1.${ uid }` : '';
 })());

_isPrototype.js

@@ -1,5 +1,5 @@
 /** Used for built-in method references. */
-var objectProto = Object.prototype;
+const objectProto = Object.prototype;
 
 /**
  * Checks if `value` is likely a prototype object.
@@ -9,8 +9,8 @@ var objectProto = Object.prototype;
  * @returns {boolean} Returns `true` if `value` is a prototype, else `false`.
  */
 function isPrototype(value) {
-  var Ctor = value && value.constructor,
+  const Ctor = value && value.constructor;
-      proto = (typeof Ctor == 'function' && Ctor.prototype) || objectProto;
+  const proto = (typeof Ctor == 'function' && Ctor.prototype) || objectProto;
 
   return value === proto;
 }

_iteratorToArray.js

@@ -6,8 +6,8 @@
  * @returns {Array} Returns the converted array.
  */
 function iteratorToArray(iterator) {
-  var data,
+  let data;
-      result = [];
+  const result = [];
 
   while (!(data = iterator.next()).done) {
     result.push(data.value);

_mapCacheDelete.js

@@ -10,7 +10,7 @@ import getMapData from './_getMapData.js';
  * @returns {boolean} Returns `true` if the entry was removed, else `false`.
  */
 function mapCacheDelete(key) {
-  var result = getMapData(this, key)['delete'](key);
+  const result = getMapData(this, key)['delete'](key);
   this.size -= result ? 1 : 0;
   return result;
 }

_mapCacheSet.js

@@ -11,8 +11,8 @@ import getMapData from './_getMapData.js';
  * @returns {Object} Returns the map cache instance.
  */
 function mapCacheSet(key, value) {
-  var data = getMapData(this, key),
+  const data = getMapData(this, key);
-      size = data.size;
+  const size = data.size;
 
   data.set(key, value);
   this.size += data.size == size ? 0 : 1;

_reEscape.js

@@ -1,4 +1,4 @@
 /** Used to match template delimiters. */
-var reEscape = /<%-([\s\S]+?)%>/g;
+const reEscape = /<%-([\s\S]+?)%>/g;
 
 export default reEscape;

_reEvaluate.js

@@ -1,4 +1,4 @@
 /** Used to match template delimiters. */
-var reEvaluate = /<%([\s\S]+?)%>/g;
+const reEvaluate = /<%([\s\S]+?)%>/g;
 
 export default reEvaluate;

_reInterpolate.js

@@ -1,4 +1,4 @@
 /** Used to match template delimiters. */
-var reInterpolate = /<%=([\s\S]+?)%>/g;
+const reInterpolate = /<%=([\s\S]+?)%>/g;
 
 export default reInterpolate;

_realNames.js

@@ -1,4 +1,4 @@
 /** Used to lookup unminified function names. */
-var realNames = {};
+const realNames = {};
 
 export default realNames;

_setData.js

@@ -15,6 +15,6 @@ import shortOut from './_shortOut.js';
  * @param {*} data The metadata.
  * @returns {Function} Returns `func`.
  */
-var setData = shortOut(baseSetData);
+const setData = shortOut(baseSetData);
 
 export default setData;

_setToArray.js

@@ -6,8 +6,8 @@
  * @returns {Array} Returns the values.
  */
 function setToArray(set) {
-  var index = -1,
+  let index = -1;
-      result = Array(set.size);
+  const result = Array(set.size);
 
   set.forEach(value => {
     result[++index] = value;

_setToString.js

@@ -9,6 +9,6 @@ import shortOut from './_shortOut.js';
  * @param {Function} string The `toString` result.
  * @returns {Function} Returns `func`.
  */
-var setToString = shortOut(baseSetToString);
+const setToString = shortOut(baseSetToString);
 
 export default setToString;

_shuffleSelf.js

@@ -9,14 +9,14 @@ import baseRandom from './_baseRandom.js';
  * @returns {Array} Returns `array`.
  */
 function shuffleSelf(array, size) {
-  var index = -1,
+  let index = -1;
-      length = array.length,
+  const length = array.length;
-      lastIndex = length - 1;
+  const lastIndex = length - 1;
 
   size = size === undefined ? length : size;
   while (++index < size) {
-    var rand = baseRandom(index, lastIndex),
+    const rand = baseRandom(index, lastIndex);
-        value = array[rand];
+    const value = array[rand];
 
     array[rand] = array[index];
     array[index] = value;

reject.js

@@ -39,7 +39,7 @@ import negate from './negate.js';
  * // => objects for ['barney']
  */
 function reject(collection, predicate) {
-  var func = isArray(collection) ? arrayFilter : baseFilter;
+  const func = isArray(collection) ? arrayFilter : baseFilter;
   return func(collection, negate(baseIteratee(predicate, 3)));
 }
 

rest.js

@@ -2,7 +2,7 @@ import baseRest from './_baseRest.js';
 import toInteger from './toInteger.js';
 
 /** Error message constants. */
-var FUNC_ERROR_TEXT = 'Expected a function';
+const FUNC_ERROR_TEXT = 'Expected a function';
 
 /**
  * Creates a function that invokes `func` with the `this` binding of the

result.js

@@ -34,8 +34,8 @@ import toKey from './_toKey.js';
 function result(object, path, defaultValue) {
   path = castPath(path, object);
 
-  var index = -1,
+  let index = -1;
-      length = path.length;
+  let length = path.length;
 
   // Ensure the loop is entered when path is empty.
   if (!length) {
@@ -43,7 +43,7 @@ function result(object, path, defaultValue) {
     object = undefined;
   }
   while (++index < length) {
-    var value = object == null ? undefined : object[toKey(path[index])];
+    let value = object == null ? undefined : object[toKey(path[index])];
     if (value === undefined) {
       index = length;
       value = defaultValue;

reverse.js

@@ -1,8 +1,8 @@
 /** Used for built-in method references. */
-var arrayProto = Array.prototype;
+const arrayProto = Array.prototype;
 
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeReverse = arrayProto.reverse;
+const nativeReverse = arrayProto.reverse;
 
 /**
  * Reverses `array` so that the first element becomes the last, the second

round.js

@@ -21,6 +21,6 @@ import createRound from './_createRound.js';
  * _.round(4060, -2);
  * // => 4100
  */
-var round = createRound('round');
+const round = createRound('round');
 
 export default round;

sample.js

@@ -17,7 +17,7 @@ import isArray from './isArray.js';
  * // => 2
  */
 function sample(collection) {
-  var func = isArray(collection) ? arraySample : baseSample;
+  const func = isArray(collection) ? arraySample : baseSample;
   return func(collection);
 }
 

sampleSize.js

@@ -30,7 +30,7 @@ function sampleSize(collection, n, guard) {
   } else {
     n = toInteger(n);
   }
-  var func = isArray(collection) ? arraySampleSize : baseSampleSize;
+  const func = isArray(collection) ? arraySampleSize : baseSampleSize;
   return func(collection, n);
 }
 

shuffle.js

@@ -18,7 +18,7 @@ import isArray from './isArray.js';
  * // => [4, 1, 3, 2]
  */
 function shuffle(collection) {
-  var func = isArray(collection) ? arrayShuffle : baseShuffle;
+  const func = isArray(collection) ? arrayShuffle : baseShuffle;
   return func(collection);
 }
 

size.js

@@ -5,8 +5,8 @@ import isString from './isString.js';
 import stringSize from './_stringSize.js';
 
 /** `Object#toString` result references. */
-var mapTag = '[object Map]',
+const mapTag = '[object Map]';
-    setTag = '[object Set]';
+const setTag = '[object Set]';
 
 /**
  * Gets the size of `collection` by returning its length for array-like
@@ -36,7 +36,7 @@ function size(collection) {
   if (isArrayLike(collection)) {
     return isString(collection) ? stringSize(collection) : collection.length;
   }
-  var tag = getTag(collection);
+  const tag = getTag(collection);
   if (tag == mapTag || tag == setTag) {
     return collection.size;
   }

slice.js

@@ -19,7 +19,7 @@ import toInteger from './toInteger.js';
  * @returns {Array} Returns the slice of `array`.
  */
 function slice(array, start, end) {
-  var length = array == null ? 0 : array.length;
+  const length = array == null ? 0 : array.length;
   if (!length) {
     return [];
   }

some.js

@@ -41,7 +41,7 @@ import isIterateeCall from './_isIterateeCall.js';
  * // => true
  */
 function some(collection, predicate, guard) {
-  var func = isArray(collection) ? arraySome : baseSome;
+  const func = isArray(collection) ? arraySome : baseSome;
   if (guard && isIterateeCall(collection, predicate, guard)) {
     predicate = undefined;
   }

sortedIndexOf.js

@@ -18,9 +18,9 @@ import eq from './eq.js';
  * // => 1
  */
 function sortedIndexOf(array, value) {
-  var length = array == null ? 0 : array.length;
+  const length = array == null ? 0 : array.length;
   if (length) {
-    var index = baseSortedIndex(array, value);
+    const index = baseSortedIndex(array, value);
     if (index < length && eq(array[index], value)) {
       return index;
     }

sortedLastIndexOf.js

@@ -18,9 +18,9 @@ import eq from './eq.js';
  * // => 3
  */
 function sortedLastIndexOf(array, value) {
-  var length = array == null ? 0 : array.length;
+  const length = array == null ? 0 : array.length;
   if (length) {
-    var index = baseSortedIndex(array, value, true) - 1;
+    const index = baseSortedIndex(array, value, true) - 1;
     if (eq(array[index], value)) {
       return index;
     }

split.js

@@ -7,7 +7,7 @@ import stringToArray from './_stringToArray.js';
 import toString from './toString.js';
 
 /** Used as references for the maximum length and index of an array. */
-var MAX_ARRAY_LENGTH = 4294967295;
+const MAX_ARRAY_LENGTH = 4294967295;
 
 /**
  * Splits `string` by `separator`.

spread.js

@@ -5,10 +5,10 @@ import castSlice from './_castSlice.js';
 import toInteger from './toInteger.js';
 
 /** Error message constants. */
-var FUNC_ERROR_TEXT = 'Expected a function';
+const FUNC_ERROR_TEXT = 'Expected a function';
 
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeMax = Math.max;
+const nativeMax = Math.max;
 
 /**
  * Creates a function that invokes `func` with the `this` binding of the
@@ -50,8 +50,8 @@ function spread(func, start) {
   }
   start = start == null ? 0 : nativeMax(toInteger(start), 0);
   return baseRest(function(args) {
-    var array = args[start],
+    const array = args[start];
-        otherArgs = castSlice(args, 0, start);
+    const otherArgs = castSlice(args, 0, start);
 
     if (array) {
       arrayPush(otherArgs, array);

startCase.js

@@ -22,6 +22,6 @@ import upperFirst from './upperFirst.js';
  * _.startCase('__FOO_BAR__');
  * // => 'FOO BAR'
  */
-var startCase = createCompounder((result, word, index) => result + (index ? ' ' : '') + upperFirst(word));
+const startCase = createCompounder((result, word, index) => result + (index ? ' ' : '') + upperFirst(word));
 
 export default startCase;

subtract.js

@@ -15,6 +15,6 @@ import createMathOperation from './_createMathOperation.js';
  * _.subtract(6, 4);
  * // => 2
  */
-var subtract = createMathOperation((minuend, subtrahend) => minuend - subtrahend, 0);
+const subtract = createMathOperation((minuend, subtrahend) => minuend - subtrahend, 0);
 
 export default subtract;

tail.js

@@ -15,7 +15,7 @@ import baseSlice from './_baseSlice.js';
  * // => [2, 3]
  */
 function tail(array) {
-  var length = array == null ? 0 : array.length;
+  const length = array == null ? 0 : array.length;
   return length ? baseSlice(array, 1, length) : [];
 }
 

takeRight.js

@@ -27,7 +27,7 @@ import toInteger from './toInteger.js';
  * // => []
  */
 function takeRight(array, n, guard) {
-  var length = array == null ? 0 : array.length;
+  const length = array == null ? 0 : array.length;
   if (!length) {
     return [];
   }

template.js

@@ -11,21 +11,21 @@ import templateSettings from './templateSettings.js';
 import toString from './toString.js';
 
 /** Used to match empty string literals in compiled template source. */
-var reEmptyStringLeading = /\b__p \+= '';/g,
+const reEmptyStringLeading = /\b__p \+= '';/g;
-    reEmptyStringMiddle = /\b(__p \+=) '' \+/g,
+const reEmptyStringMiddle = /\b(__p \+=) '' \+/g;
-    reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g;
+const reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g;
 
 /**
  * Used to match
  * [ES template delimiters](http://ecma-international.org/ecma-262/7.0/#sec-template-literal-lexical-components).
  */
-var reEsTemplate = /\$\{([^\\}]*(?:\\.[^\\}]*)*)\}/g;
+const reEsTemplate = /\$\{([^\\}]*(?:\\.[^\\}]*)*)\}/g;
 
 /** Used to ensure capturing order of template delimiters. */
-var reNoMatch = /($^)/;
+const reNoMatch = /($^)/;
 
 /** Used to match unescaped characters in compiled string literals. */
-var reUnescapedString = /['\n\r\u2028\u2029\\]/g;
+const reUnescapedString = /['\n\r\u2028\u2029\\]/g;
 
 /**
  * Creates a compiled template function that can interpolate data properties
@@ -135,7 +135,7 @@ function template(string, options, guard) {
   // Based on John Resig's `tmpl` implementation
   // (http://ejohn.org/blog/javascript-micro-templating/)
   // and Laura Doktorova's doT.js (https://github.com/olado/doT).
-  var settings = templateSettings.imports._.templateSettings || templateSettings;
+  let settings = templateSettings.imports._.templateSettings || templateSettings;
 
   if (guard && isIterateeCall(string, options, guard)) {
     options = undefined;
@@ -143,18 +143,19 @@ function template(string, options, guard) {
   string = toString(string);
   options = assignInWith({}, options, settings, customDefaultsAssignIn);
 
-  var imports = assignInWith({}, options.imports, settings.imports, customDefaultsAssignIn),
+  const imports = assignInWith({}, options.imports, settings.imports, customDefaultsAssignIn);
-      importsKeys = keys(imports),
+  const importsKeys = keys(imports);
-      importsValues = baseValues(imports, importsKeys);
+  const importsValues = baseValues(imports, importsKeys);
 
-  var isEscaping,
+  let isEscaping;
-      isEvaluating,
+  let isEvaluating;
-      index = 0,
+  let index = 0;
-      interpolate = options.interpolate || reNoMatch,
+
-      source = "__p += '";
+  const interpolate = options.interpolate || reNoMatch;
+  let source = "__p += '";
 
   // Compile the regexp to match each delimiter.
-  var reDelimiters = RegExp(
+  const reDelimiters = RegExp(
     (options.escape || reNoMatch).source + '|' +
     interpolate.source + '|' +
     (interpolate === reInterpolate ? reEsTemplate : reNoMatch).source + '|' +
@@ -162,7 +163,7 @@ function template(string, options, guard) {
   , 'g');
 
   // Use a sourceURL for easier debugging.
-  var sourceURL = 'sourceURL' in options ? `//# sourceURL=${ options.sourceURL }\n` : '';
+  const sourceURL = 'sourceURL' in options ? `//# sourceURL=${ options.sourceURL }\n` : '';
 
   string.replace(reDelimiters, (
     match,
@@ -200,7 +201,7 @@ function template(string, options, guard) {
 
   // If `variable` is not specified wrap a with-statement around the generated
   // code to add the data object to the top of the scope chain.
-  var variable = options.variable;
+  const variable = options.variable;
   if (!variable) {
     source = `with (obj) {\n${ source }\n}\n`;
   }
@@ -228,7 +229,7 @@ function template(string, options, guard) {
     source +
     'return __p\n}';
 
-  var result = attempt(() => Function(importsKeys, `${ sourceURL }return ${ source }`))(...importsValues);
+  const result = attempt(() => Function(importsKeys, `${ sourceURL }return ${ source }`))(...importsValues);
 
   // Provide the compiled function's source by its `toString` method or
   // the `source` property as a convenience for inlining compiled templates.

templateSettings.js

@@ -12,7 +12,7 @@ import reInterpolate from './_reInterpolate.js';
  * @memberOf _
  * @type {Object}
  */
-var templateSettings = {
+const templateSettings = {
 
   /**
    * Used to detect `data` property values to be HTML-escaped.

throttle.js

@@ -2,7 +2,7 @@ import debounce from './debounce.js';
 import isObject from './isObject.js';
 
 /** Error message constants. */
-var FUNC_ERROR_TEXT = 'Expected a function';
+const FUNC_ERROR_TEXT = 'Expected a function';
 
 /**
  * Creates a throttled function that only invokes `func` at most once per
@@ -49,8 +49,8 @@ var FUNC_ERROR_TEXT = 'Expected a function';
  * jQuery(window).on('popstate', throttled.cancel);
  */
 function throttle(func, wait, options) {
-  var leading = true,
+  let leading = true;
-      trailing = true;
+  let trailing = true;
 
   if (typeof func != 'function') {
     throw new TypeError(FUNC_ERROR_TEXT);

times.js

@@ -3,13 +3,13 @@ import castFunction from './_castFunction.js';
 import toInteger from './toInteger.js';
 
 /** Used as references for various `Number` constants. */
-var MAX_SAFE_INTEGER = 9007199254740991;
+const MAX_SAFE_INTEGER = 9007199254740991;
 
 /** Used as references for the maximum length and index of an array. */
-var MAX_ARRAY_LENGTH = 4294967295;
+const MAX_ARRAY_LENGTH = 4294967295;
 
 /* Built-in method references for those with the same name as other `lodash` methods. */
-var nativeMin = Math.min;
+const nativeMin = Math.min;
 
 /**
  * Invokes the iteratee `n` times, returning an array of the results of
@@ -35,13 +35,13 @@ function times(n, iteratee) {
   if (n < 1 || n > MAX_SAFE_INTEGER) {
     return [];
   }
-  var index = MAX_ARRAY_LENGTH,
+  let index = MAX_ARRAY_LENGTH;
-      length = nativeMin(n, MAX_ARRAY_LENGTH);
+  const length = nativeMin(n, MAX_ARRAY_LENGTH);
 
   iteratee = castFunction(iteratee);
   n -= MAX_ARRAY_LENGTH;
 
-  var result = baseTimes(length, iteratee);
+  const result = baseTimes(length, iteratee);
   while (++index < n) {
     iteratee(index);
   }

toArray.js

@@ -10,11 +10,11 @@ import stringToArray from './_stringToArray.js';
 import values from './values.js';
 
 /** `Object#toString` result references. */
-var mapTag = '[object Map]',
+const mapTag = '[object Map]';
-    setTag = '[object Set]';
+const setTag = '[object Set]';
 
 /** Built-in value references. */
-var symIterator = Symbol ? Symbol.iterator : undefined;
+const symIterator = Symbol ? Symbol.iterator : undefined;
 
 /**
  * Converts `value` to an array.
@@ -49,8 +49,8 @@ function toArray(value) {
   if (symIterator && value[symIterator]) {
     return iteratorToArray(value[symIterator]());
   }
-  var tag = getTag(value),
+  const tag = getTag(value);
-      func = tag == mapTag ? mapToArray : (tag == setTag ? setToArray : values);
+  const func = tag == mapTag ? mapToArray : (tag == setTag ? setToArray : values);
 
   return func(value);
 }

toFinite.js

@@ -1,8 +1,8 @@
 import toNumber from './toNumber.js';
 
 /** Used as references for various `Number` constants. */
-var INFINITY = 1 / 0,
+const INFINITY = 1 / 0;
-    MAX_INTEGER = 1.7976931348623157e+308;
+const MAX_INTEGER = 1.7976931348623157e+308;
 
 /**
  * Converts `value` to a finite number.
@@ -33,7 +33,7 @@ function toFinite(value) {
   }
   value = toNumber(value);
   if (value === INFINITY || value === -INFINITY) {
-    var sign = (value < 0 ? -1 : 1);
+    const sign = (value < 0 ? -1 : 1);
     return sign * MAX_INTEGER;
   }
   return value === value ? value : 0;

toInteger.js

@@ -27,8 +27,8 @@ import toFinite from './toFinite.js';
  * // => 3
  */
 function toInteger(value) {
-  var result = toFinite(value),
+  const result = toFinite(value);
-      remainder = result % 1;
+  const remainder = result % 1;
 
   return result === result ? (remainder ? result - remainder : result) : 0;
 }

toLength.js

@@ -2,7 +2,7 @@ import baseClamp from './_baseClamp.js';
 import toInteger from './toInteger.js';
 
 /** Used as references for the maximum length and index of an array. */
-var MAX_ARRAY_LENGTH = 4294967295;
+const MAX_ARRAY_LENGTH = 4294967295;
 
 /**
  * Converts `value` to an integer suitable for use as the length of an

toNumber.js

@@ -2,22 +2,22 @@ import isObject from './isObject.js';
 import isSymbol from './isSymbol.js';
 
 /** Used as references for various `Number` constants. */
-var NAN = 0 / 0;
+const NAN = 0 / 0;
 
 /** Used to match leading and trailing whitespace. */
-var reTrim = /^\s+|\s+$/g;
+const reTrim = /^\s+|\s+$/g;
 
 /** Used to detect bad signed hexadecimal string values. */
-var reIsBadHex = /^[-+]0x[0-9a-f]+$/i;
+const reIsBadHex = /^[-+]0x[0-9a-f]+$/i;
 
 /** Used to detect binary string values. */
-var reIsBinary = /^0b[01]+$/i;
+const reIsBinary = /^0b[01]+$/i;
 
 /** Used to detect octal string values. */
-var reIsOctal = /^0o[0-7]+$/i;
+const reIsOctal = /^0o[0-7]+$/i;
 
 /** Built-in method references without a dependency on `root`. */
-var freeParseInt = parseInt;
+const freeParseInt = parseInt;
 
 /**
  * Converts `value` to a number.
@@ -50,14 +50,14 @@ function toNumber(value) {
     return NAN;
   }
   if (isObject(value)) {
-    var other = typeof value.valueOf == 'function' ? value.valueOf() : value;
+    const other = typeof value.valueOf == 'function' ? value.valueOf() : value;
     value = isObject(other) ? `${ other }` : other;
   }
   if (typeof value != 'string') {
     return value === 0 ? value : +value;
   }
   value = value.replace(reTrim, '');
-  var isBinary = reIsBinary.test(value);
+  const isBinary = reIsBinary.test(value);
   return (isBinary || reIsOctal.test(value))
     ? freeParseInt(value.slice(2), isBinary ? 2 : 8)
     : (reIsBadHex.test(value) ? NAN : +value);