_.flip(func) source npm package Creates a function that invokes func with arguments reversed. Since 4.0.0 Arguments func (Function): The function to flip arguments for. Returns (Function): Returns the new flipped function. Example var flipped = _.flip(function() {   return _.toArray(arguments); });   flipped('a', 'b', 'c', 'd'); // => ['d', 'c', 'b', 'a']

_.flattenDepth(array, [depth=1]) source npm package Recursively flatten array up to depth times. Since 4.4.0 Arguments array (Array): The array to flatten. [depth=1] (number): The maximum recursion depth. Returns (Array): Returns the new flattened array. Example var array = [1, [2, [3, [4]], 5]];   _.flattenDepth(array, 1); // => [1, 2, [3, [4]], 5]   _.flattenDepth(array, 2); // => [1, 2, 3, [4], 5]

_.flattenDeep(array) source npm package Recursively flattens array. Since 3.0.0 Arguments array (Array): The array to flatten. Returns (Array): Returns the new flattened array. Example _.flattenDeep([1, [2, [3, [4]], 5]]); // => [1, 2, 3, 4, 5]

_.flatten(array) source npm package Flattens array a single level deep. Since 0.1.0 Arguments array (Array): The array to flatten. Returns (Array): Returns the new flattened array. Example _.flatten([1, [2, [3, [4]], 5]]); // => [1, 2, [3, [4]], 5]

_.flatMapDepth(collection, [iteratee=_.identity], [depth=1]) source npm package This method is like _.flatMap except that it recursively flattens the mapped results up to depth times. Since 4.7.0 Arguments collection (Array|Object): The collection to iterate over. [iteratee=_.identity] (Function): The function invoked per iteration. [depth=1] (number): The maximum recursion depth. Returns (Array): Returns the new flattened array. Example function duplicate(n) {   return [[[n, n]]]; }   _

_.flatMapDeep(collection, [iteratee=_.identity]) source npm package This method is like _.flatMap except that it recursively flattens the mapped results. Since 4.7.0 Arguments collection (Array|Object): The collection to iterate over. [iteratee=_.identity] (Function): The function invoked per iteration. Returns (Array): Returns the new flattened array. Example function duplicate(n) {   return [[[n, n]]]; }   _.flatMapDeep([1, 2], duplicate); // => [1, 1, 2, 2]

_.flatMap(collection, [iteratee=_.identity]) source npm package Creates a flattened array of values by running each element in collection thru iteratee and flattening the mapped results. The iteratee is invoked with three arguments: (value, index|key, collection). Since 4.0.0 Arguments collection (Array|Object): The collection to iterate over. [iteratee=_.identity] (Function): The function invoked per iteration. Returns (Array): Returns the new flattened array. Example function duplicate(

_.head(array) source npm package Gets the first element of array. Since 0.1.0 Aliases _.first Arguments array (Array): The array to query. Returns (*): Returns the first element of array. Example _.head([1, 2, 3]); // => 1   _.head([]); // => undefined

_.findLastKey(object, [predicate=_.identity]) source npm package This method is like _.findKey except that it iterates over elements of a collection in the opposite order. Since 2.0.0 Arguments object (Object): The object to inspect. [predicate=_.identity] (Function): The function invoked per iteration. Returns (*): Returns the key of the matched element, else undefined. Example var users = {   'barney':  { 'age': 36, 'active': true },   'fred':    { 'age': 40, 'active': false },   'peb

_.findLastIndex(array, [predicate=_.identity], [fromIndex=array.length-1]) source npm package This method is like _.findIndex except that it iterates over elements of collection from right to left. Since 2.0.0 Arguments array (Array): The array to inspect. [predicate=_.identity] (Function): The function invoked per iteration. [fromIndex=array.length-1] (number): The index to search from. Returns (number): Returns the index of the found element, else -1. Example var users = [   { 'user':