From 858b733ce0ef8bec79c2eaceedf8ee0204eb4c9e Mon Sep 17 00:00:00 2001 From: Ilya Kantor Date: Sat, 22 Aug 2020 10:45:44 +0300 Subject: [PATCH] Update task.md --- .../09-call-apply-decorators/03-debounce/task.md | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/1-js/06-advanced-functions/09-call-apply-decorators/03-debounce/task.md b/1-js/06-advanced-functions/09-call-apply-decorators/03-debounce/task.md index 550bf52d..fa52871a 100644 --- a/1-js/06-advanced-functions/09-call-apply-decorators/03-debounce/task.md +++ b/1-js/06-advanced-functions/09-call-apply-decorators/03-debounce/task.md @@ -6,6 +6,8 @@ importance: 5 The result of `debounce(f, ms)` decorator is a wrapper that suspends calls to `f` until there's `ms` milliseconds of inactivity (no calls, "cooldown period"), then invokes `f` once with the latest arguments. +In other words, `debounce` is like a secretary that accepts "phone calls", and waits until there's `ms` milliseconds of being quiet. And only then it transfers the latest call information to "the boss" (calls the actual `f`). + For instance, we had a function `f` and replaced it with `f = debounce(f, 1000)`. Then if the wrapped function is called at 0ms, 200ms and 500ms, and then there are no calls, then the actual `f` will be only called once, at 1500ms. That is: after the cooldown period of 1000ms from the last call. @@ -25,7 +27,6 @@ setTimeout( () => f("c"), 500); // debounced function waits 1000ms after the last call and then runs: alert("c") ``` - Now a practical example. Let's say, the user types something, and we'd like to send a request to the server when the input is finished. There's no point in sending the request for every character typed. Instead we'd like to wait, and then process the whole result. @@ -43,9 +44,8 @@ See? The second input calls the debounced function, so its content is processed So, `debounce` is a great way to process a sequence of events: be it a sequence of key presses, mouse movements or something else. - It waits the given time after the last call, and then runs its function, that can process the result. The task is to implement `debounce` decorator. -Hint: that's just a few lines if you think about it :) \ No newline at end of file +Hint: that's just a few lines if you think about it :)