JavaScript: Remove falsey values from a given array

JavaScript fundamental (ES6 Syntax): Exercise-44 with Solution

Remove Falsey Values from Array

Write a JavaScript program to remove false values from a given array.

• Use Array.prototype.filter() to filter out falsy values (false, null, 0, "", undefined, and NaN).

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2
// Define a function 'compact' that takes an array 'arr' as input and returns a new array with truthy values.
const compact = arr => 
  // Filter the elements of 'arr' using the 'Boolean' function to remove falsy values.
  arr.filter(Boolean);

// Test the 'compact' function with two arrays and log the results.
console.log(compact([0, 1, false, 2, '', 3, 'a', 'e' * 23, NaN, 's', 34])); // Output: [1, 2, 3, 'a', 's', 34]
console.log(compact([false, NaN, 'e' * 23])); // Output: []

Output:

[1,2,3,"a","s",34]
[]

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-1-44 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that filters out all falsey values (false, 0, "", null, undefined, NaN) from an array.
• Write a JavaScript function that returns a new array containing only truthy values from the given array using Boolean casting.
• Write a JavaScript program that cleans an array by removing elements that evaluate to false in a boolean context.

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