erica

import UIKit
import PlaygroundSupport
// https://gist.github.com/erica/6f13f3043a330359c035e7660f3fe7f5
// Original Video: https://www.youtube.com/watch?v=TTmWUSgNOHk
// Video: https://www.youtube.com/watch?v=hmAB3WJOQTU
// Video: https://www.youtube.com/watch?v=DWtavuvmKdw (with zoom and fade)

// String to animate and its attributes
var string = "Hello, playground"
let attributes: [String: Any] = [

andymatuschak

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,

mackuba

Following the tradition from last year, here's my complete list of all interesting features and updates I could find in Apple's OSes, SDKs and developer tools that were announced at this year's WWDC. This is based on the keynotes, the "What's New In ..." presentations and some others, Apple's release notes, and blog posts and tweets that I came across in the last few weeks.

If for some reason you haven't watched the talks yet, I really recommend watching at least the "State of the Union" and the "What's New In" intros for the platforms you're interested in. The unofficial WWDC Mac app is great way to download the videos and keep track of what you've already watched.

If you're interested, here are my WWDC 2015 notes (might be useful if you're planning to drop support for iOS 8 now and start using some iOS 9 APIs).

---

OSX → macOS 10.12 Sierra

alanzeino

LLDB Debugging Cheat Sheet

Commands

LLDB Commands

LLDB comes with a great set of commands for powerful debugging.

help

Your starting point for anything. Type help to get a list of all commands, plus any user installed ones. Type 'help for more information on a command. Type help to get help for a specific option in a command too.

blixt

import UIKit

extension String {
    var hexColor: UIColor? {
        let hex = self.stringByTrimmingCharactersInSet(NSCharacterSet.alphanumericCharacterSet().invertedSet)
        var int = UInt32()
        guard NSScanner(string: hex).scanHexInt(&int) else {
            return nil
        }
        let a, r, g, b: UInt32

ohanhi

Learning FP the hard way: Experiences on the Elm language

by Ossi Hanhinen, @ohanhi

with the support of Futurice 💚.

Licensed under CC BY 4.0.

Editorial note

harlanhaskins

Copy and paste the swift code below into a playground to experiment.

This is a very close emulation of Functor and Monad typeclasses in swift. As of Swift 1.2 and Xcode 6.3, this is no longer very fragile.

Unfortunately, the compiler cannot verify the types when passing a function to (>>=). We have to wrap the function in a closure and call it with an explicit argument to compile.

optionalDoubles >>= squareRoot // doesn't compile
optionalDoubles >>= { squareRoot($0) } // compiles

zwaldowski

OS X Developer Release Notes: Cocoa Application Framework

Notes specific to Mac OS X 10.9

Some of the major topics covered in this section include:

• Responsive scrolling
• Spaces and multiple screens
• NSStackView
• NSAppearance and light content controls

neonichu

#!/bin/sh

#ID='A16FF353-8441-459E-A50C-B071F53F51B7' # Xcode 6.2
ID='992275C1-432A-4CF7-B659-D84ED6D42D3F' # Xcode 6.3

PLIST_BUDDY=/usr/libexec/PlistBuddy

function add_compatibility() {
  "$PLIST_BUDDY" -c "Add DVTPlugInCompatibilityUUIDs:10 string $2" \
    "$1/Contents/Info.plist"

iamleeg

#!/bin/bash

git diff --cached -SNSLog --quiet

if [ $? -eq 1 ]; then
    echo "NSLog call detected, indicating debug code is staged. Please unstage your debug code."
    exit 1
fi

exit 0