React components should be pure, not "idempotent"

Summary

A blogpost in the React docs confuses idempotence with purity. Even though this might seem a small typo, it is one of essential importance in that blogpost.

Page

https://react.dev/blog/2024/02/15/react-labs-what-we-have-been-working-on-february-2024

Details

Idempotence is a property of a function that it returns the same result if you apply the function twice to itself, for example, the absolute value function abs is idempotent, since, abs(abs(x)) = x. In general terms f : X --> X is idempotent iff f ∘ f = f.

This is confused with a pure function. This is a function that, given the same input, returns the same output. It is side-effect free or written in a "functional" style.

Even if this might seem like a minor mistake; it is one of the essential properties that the compiler should check for and to that extent, especially newer developers should not be confused.

Ouvrez l’article de blog de React Labs de février 2024 lié dans l’issue et repérez la phrase qui décrit les composants React comme idempotent. Examinez l’explication environnante de la pureté, mettez à jour la terminologie afin que la page décrive correctement la propriété visée, puis vérifiez la documentation rendue.