Sometimes, we want to iterate over range in a functional way with JavaScript.
In this article, we’ll look at how to iterate over range in a functional way with JavaScript.
How to iterate over range in a functional way with JavaScript?
To iterate over range in a functional way with JavaScript, we use the array keys
method.
For instance, we write
const arr = [...Array(20).keys()].map((i) => i * i);
to create an array with 20 empty slots with Array(20)
.
Then we call keys
to return an array of indexes of the array.
And then we call map
with a callback to map the index i
to i
squared.
Conclusion
To iterate over range in a functional way with JavaScript, we use the array keys
method.