Joseph Kim joekim

## gist:598fa75e22bdfa44cf47

      
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                wincent
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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).
  

## analytics.js
// Pretend that cookies work
(function (document) {
  var cookies = {};
  document.__defineGetter__('cookie', function () {
    var output = [];
    for (var cookieName in cookies) {
      output.push(cookieName + "=" + cookies[cookieName]);
    }
    return output.join(";");
  });

## app.swift
import Cocoa


class WindowController: NSWindowController {
}

class AppDelegate: NSObject {
  var mainWindow: NSWindow?
  var mainController: NSWindowController?
}

## index.html
<!doctype html>
<html>


<head>
	<title>Industry Market Shares Treemap</title>
	<script src="http://d3js.org/d3.v3.min.js" charset="utf-8"></script>

	<style>
		h2 {

## :(
import Foundation
import ImageIO

infix operator >>= { associativity left }

func >>=<A,B>(l: A?, r: A -> B?) -> B? {
    if let x = l {
        return r(x)
    }
    return nil

## download.js
function download(fileUrl, apiPath, callback) {
        var url = require('url'),
            http = require('http'),
            p = url.parse(fileUrl),
            timeout = 10000;

        var file = fs.createWriteStream(apiPath);

        var timeout_wrapper = function( req ) {
            return function() {

## ObservationPlayground.swift
import Foundation

func weakify<T: AnyObject>(object: T, block: (T) -> Void) -> () -> Void {
    weak var weakObject = object
    return {
        if let strongObject = weakObject {
            block(strongObject)
        }
    }
}

## CGAffineTransform.swift
import Foundation

/**
 * CGAffineTransform
 *
 * var a = CGAffineTransformMakeRotation(45.0 * M_PI / 180.0)
 * var b = CGPointMake(30.0, 43.3)
 */

/**

## gist:9288f79322ed3119ece4
operator infix --> {}
func --> (instance: Any, key: String) -> Any? {
    let mirror = reflect(instance)

    for index in 0 ..< mirror.count {
        let (childKey, childMirror) = mirror[index]
        if childKey == key {
            return childMirror.value
        }
    }

## gist:e95bea13162ca0e29d4b
/* The Y combinator in Swift!

For a discussion of what the heck this is all about, see http://www.ece.uc.edu/~franco/C511/html/Scheme/ycomb.html

The nifty thing is that it allows us to implement recursion without the ability for a function to refer to itself from within its own definition.

Note how we manage a recursive definition of factorial without any function referring to its own name.

Thanks to @eridius for help with the SelfToUnderlying<T> type.
*/
	// Pretend that cookies work
	(function (document) {
	var cookies = {};
	document.__defineGetter__('cookie', function () {
	var output = [];
	for (var cookieName in cookies) {
	output.push(cookieName + "=" + cookies[cookieName]);
	}
	return output.join(";");
	});
	import Cocoa


	class WindowController: NSWindowController {
	}

	class AppDelegate: NSObject {
	var mainWindow: NSWindow?
	var mainController: NSWindowController?
	}
	<!doctype html>
	<html>


	<head>
	<title>Industry Market Shares Treemap</title>
	<script src="http://d3js.org/d3.v3.min.js" charset="utf-8"></script>

	<style>
	h2 {
	import Foundation
	import ImageIO

	infix operator >>= { associativity left }

	func >>=<A,B>(l: A?, r: A -> B?) -> B? {
	if let x = l {
	return r(x)
	}
	return nil
	function download(fileUrl, apiPath, callback) {
	var url = require('url'),
	http = require('http'),
	p = url.parse(fileUrl),
	timeout = 10000;

	var file = fs.createWriteStream(apiPath);

	var timeout_wrapper = function( req ) {
	return function() {
	import Foundation

	func weakify<T: AnyObject>(object: T, block: (T) -> Void) -> () -> Void {
	weak var weakObject = object
	return {
	if let strongObject = weakObject {
	block(strongObject)
	}
	}
	}
	import Foundation

	/**
	* CGAffineTransform
	*
	* var a = CGAffineTransformMakeRotation(45.0 * M_PI / 180.0)
	* var b = CGPointMake(30.0, 43.3)
	*/

	/**
	operator infix --> {}
	func --> (instance: Any, key: String) -> Any? {
	let mirror = reflect(instance)

	for index in 0 ..< mirror.count {
	let (childKey, childMirror) = mirror[index]
	if childKey == key {
	return childMirror.value
	}
	}
	/* The Y combinator in Swift!

	For a discussion of what the heck this is all about, see http://www.ece.uc.edu/~franco/C511/html/Scheme/ycomb.html

	The nifty thing is that it allows us to implement recursion without the ability for a function to refer to itself from within its own definition.

	Note how we manage a recursive definition of factorial without any function referring to its own name.

	Thanks to @eridius for help with the SelfToUnderlying<T> type.
	*/