Javascript Array every: Determine if All Array Elements Pass a Test

The Javascript Array.every() method tests whether all the elements of an array satisfy the given condition (a callback passed in by the user).

In essence, the every() method executes the callback function for each element of the array and returns true if all elements return true or false if only one element returns false.

const isBelowThreshold = (currentValue) => currentValue < 40;

const array1 = [1, 30, 39, 29, 10, 13];

console.log(array1.every(isBelowThreshold));
// Expected output: true

You can read more about every() method here.