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React Concept: Immutability

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What is immutability? And how does it fit in the React world?

One concept you will likely meet when programming in React is immutability (and its opposite, mutability).

It’s a controversial topic, but whatever you might think about the concept of immutability, React and most of its ecosystem kind of forces this, so you need to at least have a grasp of why it’s so important and the implications of it.

In programming, a variable is immutable when its value cannot change after it’s created.

You are already using immutable variables without knowing it when you manipulate a string. Strings are immutable by default, when you change them in reality you create a new string and assign it to the same variable name.

An immutable variable can never be changed. To update its value, you create a new variable.

The same applies to objects and arrays.

Instead of changing an array, to add a new item you create a new array by concatenating the old array, plus the new item.

An object is never updated, but copied before changing it.

This applies to React in many places.

For example, you should never mutate the state property of a component directly, but only through the setState() method.

In Redux, you never mutate the state directly, but only through reducers, which are functions.

The question is, why?

There are various reasons, the most important of which are:

Are you intimidated by Git? Can’t figure out merge vs rebase? Are you afraid of screwing up something any time you have to do something in Git? Do you rely on ChatGPT or random people’s answer on StackOverflow to fix your problems? Your coworkers are tired of explaining Git to you all the time? Git is something we all need to use, but few of us really master it. I created this course to improve your Git (and GitHub) knowledge at a radical level. A course that helps you feel less frustrated with Git. Launching May 21, 2024. Join the waiting list!
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