Functional programming with arrays Although JavaScript’s arrays are very capable out of the box, the functional paradigm improves the clarity and maintainability of array code.

Arrays provide a lot of methods. To make things easier, in this chapter, they are split into groups. The element was removed, but the array still has 3 elements, we can see that arr.length == 3.

The findIndex() method returns the index of the first element in the array that satisfies the provided callback function. Otherwise, it returns -1, indicating that no element passed the test.

Google is getting better and better at indexing JavaScript. But delays in indexing are still a massive issue. Here's what you can do.