Pure Functions in Detail

As pure functions form a fundamental principle of React, let’s explain them a little more with the help of some examples. Much of this will sound more theoretical and complex than it is in practice. However, a strong understanding of pure functions is essential for modern React developers.

Examples for a pure function

Our first function is passed a number, doubles it, and returns the result. It does not matter whether the function is being called 1, 10, or 250 times. For example, if we pass the number 5 as a value, we will receive a 10 every time. The same input always leads to the same output.