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/** * Creates a debounced function that delays invoking `func` until after `wait` * milliseconds have elapsed since the last time the debounced function was * invoked, or until the next browser frame is drawn. The debounced 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 * debounced function. Subsequent calls to the debounced 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 debounced 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 `debounce` and `throttle`. * * * // Avoid costly calculations while the window size is in flux. * jQuery(window).on('resize', debounce(calculateLayout, 150)) * * // Invoke `sendMail` when clicked, debouncing subsequent calls. * jQuery(element).on('click', debounce(sendMail, 300, { * 'leading': true, * 'trailing': false * })) * * // Ensure `batchLog` is invoked once after 1 second of debounced calls. * const debounced = debounce(batchLog, 250, { 'maxWait': 1000 }) * const source = new EventSource('/stream') * jQuery(source).on('message', debounced) * * // Cancel the trailing debounced invocation. * jQuery(window).on('popstate', debounced.cancel) * * // Check for pending invocations. * const status = debounced.pending() ? "Pending..." : "Ready" * * @format * @since 0.1.0 * @category Function * @param {Function} func The function to debounce. * @param {number} [wait=0] The number of milliseconds to delay; if omitted, `requestAnimationFrame` is used (if available). * @param {Object} [options={}] The options object. * @param {boolean} [options.leading=false] Specify invoking on the leading edge of the timeout. * @param {number} [options.maxWait] The maximum time `func` is allowed to be delayed before it's invoked. * @param {boolean} [options.trailing=true] Specify invoking on the trailing edge of the timeout. * @returns {Function} Returns the new debounced function. * @example */ export interface Options { leading?: boolean; maxWait?: number; trailing?: boolean; } declare function debounce(func: Function, wait?: number, options?: Options): { (...args: any[]): any; cancel: () => void; flush: () => any; pending: () => boolean; }; export default debounce;