• Carried on reading some more of A Complete Guide to useEffect (man it’s a long blog!)
  • Thinking about react in effects helps you understand why we might get into unintended re-renders.
  • Every re-renders is an function execution, which folds in values in the current known state. e.g when you run a setTimeout with a variable, then change the variable before the setTimeout has executed, the setTimeout ‘remembers’ the old value still!
  • useState lets you persist state between refreshes/effects. Remember when you update a value with useState this cause a re-renders!
  • useRef lets you mutate values without casing a causing re-renders
  • deps in a useEffect is a way to let React know the exact dependancies the component needs to “watch” for changes to then refresh. But don’t ever lie about deps as a workaround to prevent a refresh. This can cause unintended consequences.