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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DivineDominion

import Cocoa

/// A wrapper around any type to make Result compile
class Box<T> {
    let unbox: T
    
    init(_ value: T) {
        self.unbox = value
    }
}

erica

//
//  main.swift
//  pggrep - updated 12/4/15
//  Created by Erica Sadun on 6/17/15.
//  Copyright © 2015 Erica Sadun. All rights reserved.
//

import Foundation

extension String {

erica

import Cocoa

// Note: use of enumeration var in generic is instadeath
// Note: use of static var in generic is not yet supported

public protocol EnumConvertible: Hashable {
    init?(hashValue hash: Int)
    static func countMembers() -> Int
    static func members() -> [Self]
}

tiann

#! /usr/bin/env python
# coding: utf-8

'''
auto switch keyboard between different applications

if you want to change the app list, modify the var 'ignore_list'
'''

from AppKit import NSWorkspace, NSWorkspaceDidActivateApplicationNotification, NSWorkspaceApplicationKey

erica

import Foundation

// Extend String to support regex searching by conforming
// to CustomStringConvertible
extension String: CustomStringConvertible {
    public var description: String {return self}
}

// Regex support for keys
public extension Dictionary where Key: CustomStringConvertible {

erica

import UIKit

// Swift rewrite challenge
// Starting point: https://gist.github.com/jkereako/200342b66b5416fd715a#file-scale-and-crop-image-swift

func scaleAndCropImage(
    image: UIImage,
    toSize size: CGSize,
    fitImage: Bool = true
    ) -> UIImage {

erica

import Cocoa

// Missing isWord
func isWord(string: String) -> Bool {
    if let _ = Int(string) { return false }
    let range = NSSpellChecker.shared().checkSpelling(of: string, startingAt: 0)
    return range.location == NSNotFound
}

/*:

steipete

# The trick is to link the DeviceSupport folder from the beta to the stable version.
# sudo needed if you run the Mac App Store version. Always download the dmg instead... you'll thank me later :)

# Support iOS 15 devices (Xcode 13.0) with Xcode 12.5:
sudo ln -s /Applications/Xcode-beta.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/15.0 /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport

# Then restart Xcode and reconnect your devices. You will need to do that for every beta of future iOS versions

# (A similar approach works for older versions too, just change the version number after DeviceSupport)

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,