5 JavaScript Code Practices Your Colleagues Will Thank You for

Write clear code

Photo by Nick Fewings on Unsplash

In this article, I will go over some practices in JavaScript that will help you in the long run. You might have already heard of some (or all) of them, but it’s the details that follow below them that are most important.

Some of these examples are real-world examples taken from a production code-base. Since they were shipped to production I would like to take this opportunity to help others understand the good and the bad when we write code.

1. Handle Different Data Types

As time passes the day to realize this becomes an important practice comes closer than ever. By not handling different data types going into your functions, there is a good chance your program will suffer from errors sooner or later. You either learn by a real mistake or you learn from resources that help you avoid future mistakes.

I have come across many situations in code that look something like this:

While this runs perfectly fine without issues, what I find is that developers often read this as “default list to an empty array” and assume that this will combat errors where list was passed in as an unexpected/bad type. But JavaScript reads this as “default list to an empty array when it does not have a value to default to or when it is undefined.”

Prior to ES6, the way most of us initialized values was to use the || operator like this:

This closely resembles the behavior from the previous example and since code has shifted (conventionally) to use default parameters to do this, new developers learning JavaScript are interchanging between learning from old and new tutorials might mistake this as the same…