Installation

npm install @swyg/corre

yarn install @swyg/corre

Usage

useTimeout(...)

Calls window.setTimeout(...) declaratively.

const timeoutRef = useTimeout(
    callback: EffectCallback,
    delay: number | null,
    deps: React.DependencyList = [],
): MutableRefObject<number | null>;

If delay === null, the timer won't be set; if it's already set, it will be cleared.

If deps are passed, anytime any of them change, the previous timer will be cleared and a new one will be set. This means that:

• If no deps are passed (and this never changes), the callback will be called only once.
• If deps change faster than delay, the callback will never be called.

Note callback is stored in a ref, so you don't need to pass its dependencies as deps if you don't want the behavior just described.

useInterval(...)

Calls window.setInterval(...) declaratively.

const intervalRef = useInterval(
    callback: EffectCallback,
    delay: number | null,
    deps: React.DependencyList = [],
): MutableRefObject<number | null>

If delay === null, the timer won't be set; if it's already set, it will be cleared.

If deps are passed, anytime any of them change, the previous timer will be cleared and a new one will be set. This means that:

• If deps change faster than delay, the callback will never be called.

Note callback is stored in a ref, so you don't need to pass its dependencies as deps if you don't want the behavior just described.

useRequestAnimationFrame(...) aliased useRAF(...)

Calls window.requestAnimationFrame(...) declaratively.

const rafRef = useRequestAnimationFrame(
    callback: EffectCallback,
    isRunning: boolean,
): MutableRefObject<number | null>;

If isRunning === null, requestAnimationFrame won't be called; if it's already been called, it will be cancelled.

useThrottledRequestAnimationFrame(...) aliased useThrottledRAF(...)

Calls window.requestAnimationFrame(...) wrapped in window.setInterval(...) declaratively.

This means this callback will be called through window.requestAnimationFrame(...) once every delay ms.

const [intervalRef, rafRef] = useThrottledRequestAnimationFrame(
    callback: EffectCallback,
    delay: number | null,
    isRunning: boolean = true,
): [
    MutableRefObject<number | null>,
    MutableRefObject<number | null>,
];

If delay === null or isRunning === null, the timer won't be set and requestAnimationFrame won't be called; if it's already set / it has already been called, it will be cleared, they'll be cleared / cancelled.

If deps are passed, anytime any of them change, the previous timer will be cleared and a new one will be set. This means that:

• If deps change faster than delay, the callback will never be called.

useThrottledCallback(...)

Returns a throttled version of callback that, when called:

• Calls the original callback if it's been more than delay ms since the last call.
• Uses setTimeout to call the original callback once delay ms have passed since the last call.

const throttledFn = useThrottledCallback<A extends any[]>(
    callback: (...args: A) => void,
    delay: number,
    deps: DependencyList = [],
    options: { makeResponsive: boolean } = {}
): (...args: A) => void;

If deps are passed, anytime any of them change, the previous timer will be cleared. This means that:

• Any pending invocation of callback won't happen (unless the throttled function is called again).
• If deps change faster than delay, the callback will never be called.

Note callback is stored in a ref, so you don't need to pass its dependencies as deps if you don't want the behavior just described.

Attribution / Inspiration

• https://overreacted.io/making-setinterval-declarative-with-react-hooks/
• https://stackoverflow.com/questions/53024496/state-not-updating-when-using-react-state-hook-within-setinterval/59274004#59274004
• https://gist.github.com/Danziger/336e75b6675223ad805a88c2dfdcfd4a
• https://stackoverflow.com/a/59274004/3723993