simple2k13
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some simple functions
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TypeScript
/**
* 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;