Ricardo Pereira ricardopereira

Here's my own list of the interesting stuff announced during this year's WWDC, collected from the keynotes, various Apple docs, blog posts and tweets.

If you're planning to watch the videos, I really recommend this Mac app that helps you download and watch them: https://github.com/insidegui/WWDC.

OS X El Capitan

http://www.apple.com/osx/elcapitan-preview/

split view - two apps side by side on full screen

Better local require() paths for Node.js

Problem

When the directory structure of your Node.js application (not library!) has some depth, you end up with a lot of annoying relative paths in your require calls like:

var Article = require('../../../models/article');

Those suck for maintenance and they're ugly.

Possible solutions

A composable pattern for pure state machines with effects

State machines are everywhere in interactive systems, but they're rarely defined clearly and explicitly. Given some big blob of code including implicit state machines, which transitions are possible and under what conditions? What effects take place on what transitions?

There are existing design patterns for state machines, but all the patterns I've seen complect side effects with the structure of the state machine itself. Instances of these patterns are difficult to test without mocking, and they end up with more dependencies. Worse, the classic patterns compose poorly: hierarchical state machines are typically not straightforward extensions. The functional programming world has solutions, but they don't transpose neatly enough to be broadly usable in mainstream languages.

Here I present a composable pattern for pure state machiness with effects,

	/**
	* The following preprocessor macros can be used to adopt the new nullability annotations and generics
	* features available in Xcode 7, while maintaining backwards compatibility with earlier versions of
	* Xcode that do not support these features.
	*/

	#if __has_feature(nullability)
	# define __ASSUME_NONNULL_BEGIN NS_ASSUME_NONNULL_BEGIN
	# define __ASSUME_NONNULL_END NS_ASSUME_NONNULL_END
	# define __NULLABLE nullable

	// How to apply color formatting to your log statements:
	//
	// To set the foreground color:
	// Insert the ESCAPE_SEQ into your string, followed by "fg124,12,255;" where r=124, g=12, b=255.
	//
	// To set the background color:
	// Insert the ESCAPE_SEQ into your string, followed by "bg12,24,36;" where r=12, g=24, b=36.
	//
	// To reset the foreground color (to default value):
	// Insert the ESCAPE_SEQ into your string, followed by "fg;"

	PSPDF_EXTERN BOOL PSPDFIsBlock(id _Nullable block) {
	static Class blockClass;
	static dispatch_once_t onceToken;
	dispatch_once(&onceToken, ^{
	blockClass = [^{} class];
	while ([blockClass superclass] != NSObject.class) {
	blockClass = [blockClass superclass];
	}
	});

	#!/bin/bash

	# based on (buggy on zsh)
	#find ~/Library/Application\ Support/Developer/Shared/Xcode/Plug-ins -name Info.plist -maxdepth 3 \| xargs -I{} defaults write {} DVTPlugInCompatibilityUUIDs -array-add defaults read /Applications/Xcode.app/Contents/Info.plist DVTPlugInCompatibilityUUID

	OLD_IFS=$IFS
	IFS=$'\n'

	BETA=""

	// The trick is to copy the DeviceSupport folder from the beta to the stable version.

	cp -r /Applications/Xcode-beta.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/10.0\ \(14A5261u\) /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/

	// Then restart Xcode. You might need to do that for every beta of iOS 10/Xcode 8.