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@sebmarkbage
sebmarkbage / Infrastructure.js
Last active May 2, 2024 03:11
SynchronousAsync.js
let cache = new Map();
let pending = new Map();
function fetchTextSync(url) {
if (cache.has(url)) {
return cache.get(url);
}
if (pending.has(url)) {
throw pending.get(url);
}
@acdlite
acdlite / coordinating-async-react.md
Last active March 20, 2022 12:27
Demo: Coordinating async React with non-React views

Demo: Coordinating async React with non-React views

tl;dr I built a demo illustrating what it might look like to add async rendering to Facebook's commenting interface, while ensuring it appears on the screen simultaneous to the server-rendered story.

A key benefit of async rendering is that large updates don't block the main thread; instead, the work is spread out and performed during idle periods using cooperative scheduling.

But once you make something async, you introduce the possibility that things may appear on the screen at separate times. Especially when you're dealing with multiple UI frameworks, as is often the case at Facebook.

How do we solve this with React?

@addyosmani
addyosmani / preprocessing.md
Last active May 4, 2024 23:04
JavaScript preprocessing/precompilation

Problem: How can we preprocess JavaScript (at build-time or on the server-side) so engines like V8 don't have to spend as much time in Parse? This is a topic that involves generating either bytecode or a bytecode-like-abstraction that an engine would need to accept. For folks that don't know, modern web apps typically spend a lot longer in Parsing & Compiling JS than you may think.

  • Yoav: This can particularly be an issue on mobile. Same files getting parsed all the time for users. Theoretically if we moved the parsing work to the server-side, we would have to worry about it less.
  • One angle to this problem is we all ship too much JavaScript. That's one perspective. We could also look at preprocessing.
  • We've been talking about this topic over the last few weeks a bit with V8. There were three main options proposed.
    1. Similar to what optimize-js does. Identify IIFEs and mark them as such so the browser and VMs heuristics will catch them and do a better job than today. optimize-js only tackles IIFE bu

Minimum Viable Async with Node 6

With the release of Node 6.0.0, the surface of code that needs transpilation to use ES6 features has been reduced very dramatically.

This is what my current workflow looks like to set up a minimalistic and fast microservice using micro and async + await.

The promise

@jlongster
jlongster / immutable-libraries.md
Last active May 6, 2024 12:37
List of immutable libraries

A lot of people mentioned other immutable JS libraries after reading my post. I thought it would be good to make a list of available ones.

There are two types of immutable libraries: simple helpers for copying JavaScript objects, and actual persistent data structure implementations. My post generally analyzed the tradeoffs between both kinds of libraries and everything applies to the below libraries in either category.

Libraries are sorted by github popularity.

Persistent Data Structures w/structural sharing

@sebmarkbage
sebmarkbage / Enhance.js
Last active January 31, 2024 18:33
Higher-order Components
import { Component } from "React";
export var Enhance = ComposedComponent => class extends Component {
constructor() {
this.state = { data: null };
}
componentDidMount() {
this.setState({ data: 'Hello' });
}
render() {
@mikelehen
mikelehen / generate-pushid.js
Created February 11, 2015 17:34
JavaScript code for generating Firebase Push IDs
/**
* Fancy ID generator that creates 20-character string identifiers with the following properties:
*
* 1. They're based on timestamp so that they sort *after* any existing ids.
* 2. They contain 72-bits of random data after the timestamp so that IDs won't collide with other clients' IDs.
* 3. They sort *lexicographically* (so the timestamp is converted to characters that will sort properly).
* 4. They're monotonically increasing. Even if you generate more than one in the same timestamp, the
* latter ones will sort after the former ones. We do this by using the previous random bits
* but "incrementing" them by 1 (only in the case of a timestamp collision).
*/
@takeshixx
takeshixx / hb-test.py
Last active March 9, 2024 13:37
OpenSSL heartbeat PoC with STARTTLS support.
#!/usr/bin/env python2
"""
Author: takeshix <takeshix@adversec.com>
PoC code for CVE-2014-0160. Original PoC by Jared Stafford (jspenguin@jspenguin.org).
Supportes all versions of TLS and has STARTTLS support for SMTP,POP3,IMAP,FTP and XMPP.
"""
import sys,struct,socket
from argparse import ArgumentParser
@harith
harith / shellmarks.sh
Last active September 18, 2022 07:50
Utilities to let you easily reach frequently visited but deeply nested directories.
# Utilities for quickly accessing frequently used directories in bash.
# Usage:
# $ cd /path/to/project/src/
# $ mark code # Will create a new shortcut.
# # Becomes interactive if a shortcut already exists
# # m is an alias for mark. You can also `m code`
#
# $ code # From now on, running this anywhere in the shell
# # will put you in /path/to/project/src/code
@gmccreight
gmccreight / master.vim
Last active September 23, 2023 08:41
A script that gives you a playground for mastering vim
" copy all this into a vim buffer, save it, then...
" source the file by typing :so %
" Now the vim buffer acts like a specialized application for mastering vim
" There are two queues, Study and Known. Depending how confident you feel
" about the item you are currently learning, you can move it down several
" positions, all the way to the end of the Study queue, or to the Known
" queue.
" type ,, (that's comma comma)