Returns a memoized version of the callback that only changes if one of the inputs has changed (using ===).

Returns the current context value, as given by the nearest context provider for the given context. When the provider updates, this Hook will trigger a rerender with the latest context value.

Customize the displayed value in the devtools panel.

Accepts a function that contains imperative, possibly effectful code. The effects run after browser paint, without blocking it.

Accepts a function that contains imperative, possibly effectful code. Use this to read layout from the DOM and synchronously re-render. Updates scheduled inside useLayoutEffect will be flushed synchronously, after all DOM mutations but before the browser has a chance to paint. Prefer the standard useEffect hook when possible to avoid blocking visual updates.

Pass a factory function and an array of inputs. useMemo will only recompute the memoized value when one of the inputs has changed. This optimization helps to avoid expensive calculations on every render. If no array is provided, a new value will be computed whenever a new function instance is passed as the first argument.

An alternative to useState.

useRef returns a mutable ref object whose .current property is initialized to the passed argument (initialValue). The returned object will persist for the full lifetime of the component.

Returns a stateful value, and a function to update it.