I caught these edge cases while reading preact-ssr-prepass and hooks/src/index.js since I ran into them in react-ssr-prepass as well. While maybe a little more unexpected, some users may expect that they can throw promises in useMemo or even in useState initialisers.

This means that the hook implementation has to take into account that useMemo's factory function or useState's setup function may throw before setting up the hook state. Minor changes though;

• Flipped assignment in useReducer (hookState._value before hookState._component)
• Flipped assignments in useState (state._value before state._args)