Q
What is the result of _.map([1, 2, 3], function(num) { return num * 3; })?

Answer & Solution

Answer: Option B
Solution:
The _.map function produces a new array of values by mapping each value in a list through a transformation function.
Related Questions on Average

Which function is used to clone an object in Underscore.js?

A). _.extend

B). _.clone

C). _.map

D). _.filter

Which function retrieves the minimum value in a list using Underscore.js?

A). _.min

B). _.max

C). _.reduce

D). _.filter

How can you invoke a function a specified number of times in Underscore.js?

A). _.times

B). _.invoke

C). _.repeat

D). _.cycle

How do you shuffle the elements of an array in Underscore.js?

A). _.each

B). _.shuffle

C). _.sample

D). _.random

What does _.pluck([{a: 1}, {a: 2}, {a: 3}], 'a') return?

A). [1, 2, 3]

B). [1, 2]

C). [2, 3]

D). [3, 1]

What does _.keys({one: 1, two: 2, three: 3}) return?

A). [1, 2, 3]

B). ['one', 'two', 'three']

C). ['1', '2', '3']

D). [1, 2, 'three']

How do you check if a value is an array in Underscore.js?

A). _.isObject

B). _.isArray

C). _.isArguments

D). _.isString

How do you flatten a nested array using Underscore.js?

A). _.map

B). _.flatten

C). _.filter

D). _.reduce

How do you debounce a function in Underscore.js to limit the rate at which it can fire?

A). _.throttle

B). _.debounce

C). _.delay

D). _.once

What is the result of _.reduce([1, 2, 3], function(sum, num) { return sum + num; }, 0)?

A). 6

B). 5

C). 3

D). 2