Tennison Chan tennisonchan

2015-01-29 Unofficial Relay FAQ

Compilation of questions and answers about Relay from React.js Conf.

Disclaimer: I work on Relay at Facebook. Relay is a complex system on which we're iterating aggressively. I'll do my best here to provide accurate, useful answers, but the details are subject to change. I may also be wrong. Feedback and additional questions are welcome.

What is Relay?

Relay is a new framework from Facebook that provides data-fetching functionality for React applications. It was announced at React.js Conf (January 2015).

	// ----------------------------------------------------------
	// A short snippet for detecting versions of IE in JavaScript
	// without resorting to user-agent sniffing
	// ----------------------------------------------------------
	// If you're not in IE (or IE version is less than 5) then:
	// ie === undefined
	// If you're in IE (>=5) then you can determine which version:
	// ie === 7; // IE7
	// Thus, to detect IE:
	// if (ie) {}

	// http://phantomjs.org/screen-capture.html
	// phantomjs rasterize.js https://google.com google.png

	var page = require('webpage').create(),
	system = require('system'),
	address, output, size;

	if (system.args.length < 3 \|\| system.args.length > 5) {
	console.log('Usage: rasterize.js URL filename [paperwidth*paperheight\|paperformat] [zoom]');
	console.log(' paper (pdf output) examples: "5in7.5in", "10cm20cm", "A4", "Letter"');

	/*
	* object.watch polyfill
	*
	* 2012-04-03
	*
	* By Eli Grey, http://eligrey.com
	* Public Domain.
	* NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.
	*/

	// http://phantomjs.org/screen-capture.html
	// phantomjs rasterize.js https://google.com google.png

	var page = require('webpage').create(),
	system = require('system'),
	address, output, size;

	var userAgents = {
	'Chrome': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.99 Safari/537.36'
	}

	fib = [1,2,3,5,8,13,21,34,55,89,144];

	function dec2fib(num) {
	list = [];
	for(var i=fib.length;i<0;i--){
	if(fib[i] < num){
	num -= fib[i];
	list.push(i);
	}
	}

	<!DOCTYPE html>
	<html>
	<head>
	<title></title>
	</head>
	<style type="text/css">

	.css-filter-target {
	-webkit-filter: hue-rotate(90deg);
	filter: hue-rotate(90deg);

	var Player = function(name, match_table){
	this.name = name;
	this.rounds = [];
	this.output_options = [];
	this.score = 0;

	this.init = function () {
	for(var opt in match_table){
	this.output_options.push(opt);
	}

	// Regardless of where they occur in the function scope,
	// it will be hoisted to the top.
	// it looks like this

	var foo = 1;

	function bar() {
	if (!foo) {
	var foo = 10;
	}

	var timeout20 = null;
	var timeout50 = null;

	onscroll = function(e){
	var scrollPosition = window.scrollY / (window.document.body.scrollHeight - window.innerHeight);
	if(0.2 < scrollPosition && scrollPosition < 0.5){
	clearTimeout(timeout20);
	timeout20 = setTimeout(function(){
	console.log('20%');
	}, 500);