import { CallOptions, DebouncedState } from './useDebouncedCallback'; /** * Creates a throttled function that only invokes `func` at most once per * every `wait` milliseconds (or once per browser frame). * * The throttled function comes with a `cancel` method to cancel delayed `func` * invocations and a `flush` method to immediately invoke them. * * Provide `options` to indicate whether `func` should be invoked on the leading * and/or trailing edge of the `wait` timeout. The `func` is invoked with the * last arguments provided to the throttled function. * * Subsequent calls to the throttled function return the result of the last * `func` invocation. * * **Note:** If `leading` and `trailing` options are `true`, `func` is * invoked on the trailing edge of the timeout only if the throttled function * is invoked more than once during the `wait` timeout. * * If `wait` is `0` and `leading` is `false`, `func` invocation is deferred * until the next tick, similar to `setTimeout` with a timeout of `0`. * * If `wait` is omitted in an environment with `requestAnimationFrame`, `func` * invocation will be deferred until the next frame is drawn (typically about * 16ms). * * See [David Corbacho's article](https://css-tricks.com/debouncing-throttling-explained-examples/) * for details over the differences between `throttle` and `debounce`. * * @category Function * @param {Function} func The function to throttle. * @param {number} [wait=0] * The number of milliseconds to throttle invocations to; if omitted, * `requestAnimationFrame` is used (if available, otherwise it will be setTimeout(...,0)). * @param {Object} [options={}] The options object. * @param {boolean} [options.leading=true] * Specify invoking on the leading edge of the timeout. * @param {boolean} [options.trailing=true] * Specify invoking on the trailing edge of the timeout. * @returns {Function} Returns the new throttled function. * @example * * // Avoid excessively updating the position while scrolling. * const scrollHandler = useThrottledCallback(updatePosition, 100) * window.addEventListener('scroll', scrollHandler) * * // Invoke `renewToken` when the click event is fired, but not more than once every 5 minutes. * const { callback } = useThrottledCallback(renewToken, 300000, { 'trailing': false }) * * * // Cancel the trailing throttled invocation. * window.addEventListener('popstate', throttled.cancel); */ export default function useThrottledCallback ReturnType>(func: T, wait: number, { leading, trailing }?: CallOptions): DebouncedState;