Lodash _.compact() Function

Lodash proves to be much useful when working with arrays, strings, objects etc. It makes math operations and function paradigm much easier, concise. The _.compact() function is used to creates an array with all falsey values removed in JavaScript.

Syntax:

_.compact(array)

Parameters: This function accepts only a single parameter as mentioned above and described below:

• array: It is an array to be compacted.

Note: The values false, null, 0, “”, undefined, and NaN are falsey.

Return Value: This function returns the array after filtering the values.

Few examples are given below for a better understanding of the function.

Example 1: Passing a list of both the true and the false elements to _.compact() function.

javascript

// Requiring the lodash library
let lodash = require("lodash");

// Original array to be compacted
let array = [0, 1, false, 2, '', 3];

let newArray = lodash.compact(array);
console.log("Before compact: " + array);

// Printing newArray
console.log("After compact: " + newArray);

Output:

Example 2: Passing a list containing all the false values to the _.compact() function.

javascript

// Requiring the lodash library
let lodash = require("lodash");

// Original array to be compacted
let array = [0, false, '', undefined, NaN];

let newArray = lodash.compact(array);
console.log("Before compact: " + array);

// Printing newArray
console.log("After compact: " + newArray);

Output:

Example 3: Passing a list which contains a false element in ” to _.compact() function.

javascript

// Requiring the lodash library
let lodash = require("lodash");

// Original array to be compacted
let array = [false, 'HTML', NaN,
                       'CSS', 'undefined'];

let newArray = lodash.compact(array);
console.log("Before compact: " + array);

// Printing newArray
console.log("After compact: " + newArray);

Output:

Example 4: Passing a list containing modified false values to the _.reduce() function.

javascript

// Requiring the lodash library
let lodash = require("lodash");

// Original array to be compacted
let array = [false, true, 'yes', 'no', "no2"];

let newArray = lodash.compact(array);
console.log("Before compact: " + array);

// Printing newArray
console.log("After compact: " + newArray);

Output: