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,

madhavajay

# VERSION 1.0.4
# Author: @madhavajay
# This currently works for iOS and watchOS in the Simulator and Devices

# Changes
# Using ${TOOLCHAIN} in two places now
# Added double quotes " around paths
# Fixed watchOS Issues

# Instructions iOS

cecilemuller

How to setup Let's Encrypt for Nginx on Ubuntu 18.04 (including IPv6, HTTP/2 and A+ SLL rating)

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Virtual hosts

Let's say you want to host domains first.com and second.com.

Create folders for their files:

chriseidhof

//  Created by Chris Eidhof on 04-01-16.
//  Copyright © 2016 Chris Eidhof. All rights reserved.
//
// Large parts copy/pasted from https://github.com/Eonil/TCPIPSocket.Swift

import Foundation

struct TCPIPSocketAddress {
    init(_ a:UInt8, _ b:UInt8, _ c:UInt8, _ d:UInt8) {
        let	a1	=	UInt32(a) << 24

NachoSoto

//
//  Signal+Extensions.swift
//  Khan Academy
//
//  Created by Nacho Soto on 10/1/15.
//  Copyright © 2015 Khan Academy. All rights reserved.
//

import ReactiveCocoa

Dania02525

defmodule Repo.Migrations.CreateProcedures do @doc """
Creates procedure to get and update a local_id number on SaaS apps where
next local id is stored in the tenant table.

Example trigger is given  for the user table
"""
  use Ecto.Migration
 
  def up do
    execute "CREATE OR REPLACE FUNCTION get_local_id(tenant_id integer) RETURNS integer AS $$ 

mikeash

import Foundation


protocol Serializable {
    static func deserializeInto(bytePtr: UnsafeMutablePointer<UInt8>, bytes: ArraySlice<UInt8>) -> ArraySlice<UInt8>
}

extension Serializable {
    typealias WorkaroundSelf = Self
    

isaacs

# Hello, and welcome to makefile basics.
#
# You will learn why `make` is so great, and why, despite its "weird" syntax,
# it is actually a highly expressive, efficient, and powerful way to build
# programs.
#
# Once you're done here, go to
# http://www.gnu.org/software/make/manual/make.html
# to learn SOOOO much more.

rwz

# config/initializers/lol_json.rb

module ActiveSupport
  module JSON
    module Encoding
      class JSONGemEncoder
        BYPASS_JSONIFY = Set.new
        
        alias_method :original_jsonify, :jsonify
        

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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