(by @andrestaltz)
If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.
(by @andrestaltz)
If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.
All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.
Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.
elem.offsetLeft
, elem.offsetTop
, elem.offsetWidth
, elem.offsetHeight
, elem.offsetParent
/* | |
* This work is free. You can redistribute it and/or modify it under the | |
* terms of the Do What The Fuck You Want To Public License, Version 2, | |
* as published by Sam Hocevar. See the COPYING file for more details. | |
*/ | |
/* | |
* Easing Functions - inspired from http://gizma.com/easing/ | |
* only considering the t value for the range [0, 1] => [0, 1] | |
*/ | |
EasingFunctions = { |
L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns
Compress 1K bytes with Zippy ............. 3,000 ns = 3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns = 20 µs
SSD random read ........................ 150,000 ns = 150 µs
Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs
I recently had several days of extremely frustrating experiences with service workers. Here are a few things I've since learned which would have made my life much easier but which isn't particularly obvious from most of the blog posts and videos I've seen.
I'll add to this list over time – suggested additions welcome in the comments or via twitter.com/rich_harris.
Chrome 51 has some pretty wild behaviour related to console.log
in service workers. Canary doesn't, and it has a load of really good service worker related stuff in devtools.
A lot of people misunderstood Top-level await is a footgun, including me. I thought the primary danger was that people would be able to put things like AJAX requests in their top-level await
expressions, and that this was terrible because await
strongly encourages sequential operations even though a lot of the asynchronous activity we're talking about should actually happen concurrently.
But that's not the worst of it. Imperative module loading is intrinsically bad for app startup performance, in ways that are quite subtle.
Consider an app like this:
// main.js
This is definitely not the first time I've written about this topic, but I haven't written formally about it in quite awhile. So I want to revisit why I think technical-position interviewing is so poorly designed, and lay out what I think would be a better process.
I'm just one guy, with a bunch of strong opinions and a bunch of flaws. So take these suggestions with a grain of salt. I'm sure there's a lot of talented, passionate folks with other thoughts, and some are probably a lot more interesting and useful than my own.
But at the same time, I hope you'll set aside the assumptions and status quo of how interviewing is always done. Just because you were hired a certain way, and even if you liked it, doesn't mean that it's a good interview process to repeat.
If you're happy with the way technical interviewing currently works at your company, fine. Just stop, don't read any further. I'm not going to spend any effort trying to convince you otherwise.
:root { | |
--ease-in-quad: cubic-bezier(.55, .085, .68, .53); | |
--ease-in-cubic: cubic-bezier(.550, .055, .675, .19); | |
--ease-in-quart: cubic-bezier(.895, .03, .685, .22); | |
--ease-in-quint: cubic-bezier(.755, .05, .855, .06); | |
--ease-in-expo: cubic-bezier(.95, .05, .795, .035); | |
--ease-in-circ: cubic-bezier(.6, .04, .98, .335); | |
--ease-out-quad: cubic-bezier(.25, .46, .45, .94); | |
--ease-out-cubic: cubic-bezier(.215, .61, .355, 1); |