map_.map(list, iteratee, [context]) Alias: collect Produces a new array of values by mapping each value in list through a transformation function (iteratee). The iteratee is passed three arguments: the value, then the index (or key) of the iteration, and finally a reference to the entire list. _.map([1, 2, 3], function(num){ return num * 3; }); => [3, 6, 9] _.map({one: 1, two: 2, three: 3}, function(num, key){ return num * 3; }); => [3, 6, 9] _.map([[1, 2], [3, 4]], _.first); => [1

bind_.bind(function, object, *arguments) Bind a function to an object, meaning that whenever the function is called, the value of this will be the object. Optionally, pass arguments to the function to pre-fill them, also known as partial application. For partial application without context binding, use partial. var func = function(greeting){ return greeting + ': ' + this.name }; func = _.bind(func, {name: 'moe'}, 'hi'); func(); => 'hi: moe'

constant_.constant(value) Creates a function that returns the same value that is used as the argument of _.constant. var stooge = {name: 'moe'}; stooge === _.constant(stooge)(); => true

result_.result(object, property, [defaultValue]) If the value of the named property is a function then invoke it with the object as context; otherwise, return it. If a default value is provided and the property doesn't exist or is undefined then the default will be returned. If defaultValue is a function its result will be returned. var object = {cheese: 'crumpets', stuff: function(){ return 'nonsense'; }}; _.result(object, 'cheese'); => "crumpets" _.result(object, 'stuff'); => "nonse

defaults_.defaults(object, *defaults) Fill in undefined properties in object with the first value present in the following list of defaults objects. var iceCream = {flavor: "chocolate"}; _.defaults(iceCream, {flavor: "vanilla", sprinkles: "lots"}); => {flavor: "chocolate", sprinkles: "lots"}

unzip_.unzip(array) The opposite of zip. Given an array of arrays, returns a series of new arrays, the first of which contains all of the first elements in the input arrays, the second of which contains all of the second elements, and so on. _.unzip([["moe", 30, true], ["larry", 40, false], ["curly", 50, false]]); => [['moe', 'larry', 'curly'], [30, 40, 50], [true, false, false]]

debounce_.debounce(function, wait, [immediate]) Creates and returns a new debounced version of the passed function which will postpone its execution until after wait milliseconds have elapsed since the last time it was invoked. Useful for implementing behavior that should only happen after the input has stopped arriving. For example: rendering a preview of a Markdown comment, recalculating a layout after the window has stopped being resized, and so on. At the end of the wait interval, the f

sortBy_.sortBy(list, iteratee, [context]) Returns a (stably) sorted copy of list, ranked in ascending order by the results of running each value through iteratee. iteratee may also be the string name of the property to sort by (eg. length). _.sortBy([1, 2, 3, 4, 5, 6], function(num){ return Math.sin(num); }); => [5, 4, 6, 3, 1, 2] var stooges = [{name: 'moe', age: 40}, {name: 'larry', age: 50}, {name: 'curly', age: 60}]; _.sortBy(stooges, 'name'); => [{name: 'curly', age: 60}, {name:

max_.max(list, [iteratee], [context]) Returns the maximum value in list. If an iteratee function is provided, it will be used on each value to generate the criterion by which the value is ranked. -Infinity is returned if list is empty, so an isEmpty guard may be required. var stooges = [{name: 'moe', age: 40}, {name: 'larry', age: 50}, {name: 'curly', age: 60}]; _.max(stooges, function(stooge){ return stooge.age; }); => {name: 'curly', age: 60};

groupBy_.groupBy(list, iteratee, [context]) Splits a collection into sets, grouped by the result of running each value through iteratee. If iteratee is a string instead of a function, groups by the property named by iteratee on each of the values. _.groupBy([1.3, 2.1, 2.4], function(num){ return Math.floor(num); }); => {1: [1.3], 2: [2.1, 2.4]} _.groupBy(['one', 'two', 'three'], 'length'); => {3: ["one", "two"], 5: ["three"]}