| > As for the empty array of dependencies to emulate the previous componentDidMount method, this was indeed the original message in 2019. I am almost certain — though I can't find this online now — that Dan Abramov subsequently tweeted to not rely on the empty dependencies array as a guarantee that the useEffect only fires once per component's lifetime. This is one of the big reasons why I personally dislike React and the community around it. They seem to envision at the start certain ways to do things, and push them to the point of being "this is how you do X". Then, after not very long at all, the old way is discovered to be bad and inefficient and buggy and hard to reason about or whatever, now do it this other way. Repeat three or four times until a new API is created or something. This also means that going from project to project can feel very whiplash-inducing. The code you find is not even dependant on the version of React that's installed, but on how the community was feeling about the "best practices" around the time that particular project was started. I remember when render props were a thing. Then I remember when they stopped being considered a thing and now the new thing to do was HOCs. Things like React Router also being wildly different between versions, or at least v3 -> v4. I remember needing to find out how to achieve certain behaviour with v3, only to then try to find that the docs only existed for v4 (which was the newest at the time), and addons that helped me with my original problem also only existed for v4. (Then React Router was no longer the Best Thing, so let's all switch to Reach Router... then back to React Router when it was again considered the new hotness. I may have forgotten one or two others in there, I just stopped paying attention around that point.) Another example is CSS scoping, which is a complete non-issue with vanilla Vue and Svelte. But in React land you have styled-components, emotion, styled-jsx, and who knows what else in which you don't write CSS, but JS that looks like CSS but not quite, enough to throw me off every single time. The whole periodic shifting of opinions about useEffect from "this is your componentDidUpdate replacement" to "use a linter to warn you about the footguns that we can no longer fix, also use one of these hooks instead" is just one more thing that adds to the frustration of having to work with a React-based project. I'm actually starting to wonder if Facebook isn't so much "writing" React, but "discovering" it. Much like how we didn't quite invent fire, and we had to figure out how to use it properly over many, many thousands of years. |