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use lazy state initialization to avoid eager deref calculation #95

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use lazy state initialization to avoid eager deref calculation #95

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4 changes: 2 additions & 2 deletions src/dependencies/useStoreDependency.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -83,9 +83,9 @@ function useStoreDependency<Props, DepType>(
): DepType {
enforceDispatcher(dispatcher);

const [dependencyValue, setDependencyValue] = useState({
const [dependencyValue, setDependencyValue] = useState(() => ({
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@gmcnaughton gmcnaughton Feb 18, 2021

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This is 💯 !

The only other tweak we could consider is literally moving the const newValue = { dependency: ... } up above here, then reusing newValue both as the initial state and where it is already used. That has the added benefit of skipping an extra eval of the deref in the opposite case (where we are initializing state for the first time)

dependency: calculate(dependency, props),
});
}));

const currProps = useCurrent(props);

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