VictorTaelin

async/await is just the do-notation of the Promise monad

CertSimple just wrote a blog post arguing ES2017's async/await was the best thing to happen with JavaScript. I wholeheartedly agree.

In short, one of the (few?) good things about JavaScript used to be how well it handled asynchronous requests. This was mostly thanks to its Scheme-inherited implementation of functions and closures. That, though, was also one of its worst faults, because it led to the "callback hell", an seemingly unavoidable pattern that made highly asynchronous JS code almost unreadable. Many solutions attempted to solve that, but most failed. Promises almost did it, but failed too. Finally, async/await is here and, combined with Promises, it solves the problem for good. On this post, I'll explain why that is the case and trace a link between promises, async/await, the do-notation and monads.

First, let's illustrate the 3 styles by implementing

bcardiff

unless ARGV.size > 0
  puts "  Missing executable file argument"
  puts "  Usage (in a Dockerfile)"
  puts "  RUN crystal run ./path/to/list-deps.cr -- ./bin/executable"
  exit 1
end

executable = File.expand_path(ARGV[0])

unless File.exists?(executable)

Jamesits

# Should work on all Debian based distros with systemd; tested on Ubuntu 16.04+.
# This will by default install all plugins; you can customize this behavior on line 6. Selecting too many plugins can cause issues when downloading. 
# Run as root (or sudo before every line) please. Note this is not designed to be run automatically; I recommend executing this line by line.

apt install curl
curl https://getcaddy.com | bash -s personal dns,docker,dyndns,hook.service,http.authz,http.awses,http.awslambda,http.cache,http.cgi,http.cors,http.datadog,http.expires,http.filemanager,http.filter,http.forwardproxy,http.geoip,http.git,http.gopkg,http.grpc,http.hugo,http.ipfilter,http.jekyll,http.jwt,http.locale,http.login,http.mailout,http.minify,http.nobots,http.prometheus,http.proxyprotocol,http.ratelimit,http.realip,http.reauth,http.restic,http.upload,http.webdav,net,tls.dns.auroradns,tls.dns.azure,tls.dns.cloudflare,tls.dns.cloudxns,tls.dns.digitalocean,tls.dns.dnsimple,tls.dns.dnsmadeeasy,tls.dns.dnspod,tls.dns.dyn,tls.

SimplGy

#!/bin/bash
# TODO: skip tiny files (so small they couldn't be photos)
# TODO: make sure sym links and other file system oddities are handled
# TODO: look at paralellization for perf boost

#
# Constants
#
CHAR_COUNT=12
BLOCK_COUNT=6

avafloww

/*<?php
//*/public class PhpJava { public static void main(String[] args) { System.out.printf("/*%s",
//\u000A\u002F\u002A
class PhpJava {
    static function main() {
        echo(//\u000A\u002A\u002F
        "Hello World!");
}}
//\u000A\u002F\u002A
PhpJava::main();

nathan-osman

package main

import (
	"log"
	"syscall"
	"unsafe"
)

var (
	kernel32 = syscall.NewLazyDLL("kernel32.dll")

leommoore

MongoDB 3.2.x SSL with Letsencrypt

Letsencrypt is an initative which aims to increase the use of encryption for websites. It basically allows people to apply for free certificates provided that they prove the they control the requested domain. We will look at the what is needed to secure your MongoDB installation. For more details on setting up a MongoDB server see MongoDB 3.2.x.

Set the hostname

We sould to set the hostname to match the name of the certificate we are going to optain.

sudo hostname mongo0.example.com

Then update the hostname file to set the server name permanently.

vasanthk

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?

piotr-yuxuan

(ns firstshot.chessknightmove
  (:refer-clojure :exclude [== >= <= > < =])
  (:use clojure.core.logic
        clojure.core.logic.arithmetic))

(defn knight-moves
  "Returns the available moves for a knight (on a 8x8 grid) given its current position."
  [x y]
  (let [xmax 8 ymax 8]
    (run* [q]

v9n

#!/bin/bash

# --------------------------------
# Totally Simple Web Server (TSWS)
# --------------------------------
#
#  (c) 2015 Dave Fletcher
#  All Rights Reserved
#
#  This is free and unencumbered software released into the public domain.