Our code gets more readable if we make it more abstract. We don't need to know how they work as long as it works. Many u...

We often need to build similar structures in different objects. Some functions require the same variables but want to ha...

Null check in many places is tedious. This post shows you how to reduce such work in a nice way.

Explains how to get value by key, get key by value, and use an enum as an object key. Some functions don't behave as expected when an enum has number values or mixed type data. All enum-related solutions are on this page.

The spread operator (three dots) is used to copy an array and expand an array to pass the values to another object or function parameters. It can also be used as rest parameters in a function to indicate that the function can take as many arguments as you want. The spread operator is handled as a shallow copy. Therefore you need to be careful if you use it for an object that has objects in the property list.

try-catch doesn't catch an error thrown in timer friend functions setTimeout, setInterval and setImmediate. Using timer ...

Recursive setTimeout and setInterval behave differently. You need to know the difference and which to use depending on the specification. This post explains how to implement it and the difference with images.