staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

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This tutorial as a series of videos

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.

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jrochkind

A Capistrano Rails Guide

by Jonathan Rochkind, http://bibwild.wordpress.com

why cap?

Capistrano automates pushing out a new version of your application to a deployment location.

I've been writing and deploying Rails apps for a while, but I avoided using Capistrano until recently. I've got a pretty simple one-host deployment, and even though everyone said Capistrano was great, every time I tried to get started I just got snowed under not being able to figure out exactly what I wanted to do, and figured I wasn't having that much trouble doing it "manually".

slikts

Why using the children prop makes React.memo() not work

I've recently ran into a pitfall of [React.memo()][memo] that seems generally overlooked; skimming over the top results in Google just finds it mentioned in passing in a [React issue][regit], but not in the [FAQ] or API [overview][react-api], and not in the articles that set out to explain React.memo() (at least the ones I looked at). The issue is specifically that nesting children defeats memoization, unless the children are just plain text. To give a simplified code example:

const Memoized = React.memo(({ children }) => (<div>{children}</div>));
// Won't ever re-render
<Memoized>bar</Memoized>
// Will re-render every time; the memoization does nothing

slikts

Advanced memoization and effects in React

Memoization is a somewhat fraught topic in the React world, meaning that it's easy to go wrong with it, for example, by [making memo() do nothing][memo-pitfall] by passing in children to a component. The general advice is to avoid memoization until the profiler tells you to optimize, but not all use cases are general, and even in the general use case you can find tricky nuances.

Discussing this topic requires some groundwork about the technical terms, and I'm placing these in once place so that it's easy to skim and skip over:

• Memoization means caching the output based on the input; in the case of functions, it means caching the return value based on the arguments.
• Values and references are unfortunately overloaded terms that can refer to the low-level implementation details of assignments in a language like C++, for example, or to memory

zziuni

# source : http://code.google.com/p/natvpn/source/browse/trunk/stun_server_list
# A list of available STUN server.

stun.l.google.com:19302
stun1.l.google.com:19302
stun2.l.google.com:19302
stun3.l.google.com:19302
stun4.l.google.com:19302
stun01.sipphone.com
stun.ekiga.net

fokusferit

Shallow

Real unit test (isolation, no children render)

Simple shallow

Calls:

• constructor
• render

justintv

# If you work with git, you've probably had that nagging sensation of not knowing what branch you are on. Worry no longer!

export PS1="\\w:\$(git branch 2>/dev/null | grep '^*' | colrm 1 2)\$ "

# This will change your prompt to display not only your working directory but also your current git branch, if you have one. Pretty nifty!

# ~/code/web:beta_directory$ git checkout master
# Switched to branch "master"
# ~/code/web:master$ git checkout beta_directory
# Switched to branch "beta_directory"

yetithefoot

{url:'stun:stun01.sipphone.com'},
{url:'stun:stun.ekiga.net'},
{url:'stun:stun.fwdnet.net'},
{url:'stun:stun.ideasip.com'},
{url:'stun:stun.iptel.org'},
{url:'stun:stun.rixtelecom.se'},
{url:'stun:stun.schlund.de'},
{url:'stun:stun.l.google.com:19302'},
{url:'stun:stun1.l.google.com:19302'},
{url:'stun:stun2.l.google.com:19302'},

thomd

Public APIs

• https://github.com/public-apis/public-apis (A collective list of free APIs)
• https://github.com/n0shake/Public-APIs
• https://github.com/toddmotto/public-apis (huge list of public APIs)
• http://openweathermap.org
• https://market.mashape.com
• http://numbersapi.com (An API for interesting facts about numbers)
• http://fixer.io (JSON API for foreign exchange rates and currency conversion)
• http://restcountries.eu (Get information about countries)

demisx

Provider	Singleton	Instantiable	Configurable
Constant	Yes	No	No
Value	Yes	No	No
Service	Yes	No	No
Factory	Yes	Yes	No
Decorator	Yes	No?	No
Provider	Yes	Yes	Yes

Constant