klaaspieter

From time to time, Musk will send out an e-mail to the entire company to enforce a new policy or let them know about something that's bothering him. One of the more famous e-mails arrived in May 2010 with the subject line: Acronyms Seriously Suck:

There is a creeping tendency to use made up acronyms at SpaceX. Excessive use of made up acronyms is a significant impediment to communication and keeping communication good as we grow is incredibly important. Individually, a few acronyms here and there may not seem so bad, but if a thousand people are making these up, over time the result will be a huge glossary that we have to issue to new employees. No one can actually remember all these acronyms and people don't want to seem dumb in a meeting, so they just sit there in ignorance. This is particularly tough on new employees.

That needs to stop immediately or I will take drastic action - I have given enough warning over the years. Unless an acronym is approved by me, it should not enter the SpaceX glossary.

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,

davidchambers

var convertPercentage = function(percentage) {
  if (percentage == null) {
    return null;
  } else {
    return parseFloat(percentage.replace(/[^-\d.]/g, ''));
  }
};

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?

Avaq

const I  = x => x
const K  = x => y => x
const A  = f => x => f (x)
const T  = x => f => f (x)
const W  = f => x => f (x) (x)
const C  = f => y => x => f (x) (y)
const B  = f => g => x => f (g (x))
const S  = f => g => x => f (x) (g (x))
const S_ = f => g => x => f (g (x)) (x)
const S2 = f => g => h => x => f (g (x)) (h (x))

DrBoolean

// http://www.haskellforall.com/2013/02/you-could-have-invented-comonads.html

const daggy = require('daggy');
const {toUpper, prop, identity, range, curry, compose} = require('ramda');

const Config = daggy.tagged("opts")

Config.prototype.inspect = function() {
  return `Config(${this.opts})`
}

vmlinz

Intro

• https://en.wikipedia.org/wiki/Comparison_of_free_software_e-commerce_web_application_frameworks
• https://www.djangopackages.com/grids/g/ecommerce/
• https://www.mindmeister.com/66865574/ecommerce-organization

List of open source ecommerce platforms

• https://www.magentocommerce.com/
• https://www.opencart.com/

tobiassteenweg

extension String {
    
    func encodeURIComponent() -> String? {
        var characterSet = NSMutableCharacterSet.alphanumericCharacterSet()
        characterSet.addCharactersInString("-_.!~*'()")

        return self.stringByAddingPercentEncodingWithAllowedCharacters(characterSet)
    }
}

nolanlawson

// Promise.all is good for executing many promises at once
Promise.all([
  promise1,
  promise2
]);

// Promise.resolve is good for wrapping synchronous code
Promise.resolve().then(function () {
  if (somethingIsNotRight()) {
    throw new Error("I will be rejected asynchronously!");

CodaFi

// Playground - noun: a place where people can play

public func id<A>(x : A) -> A {
	return x
}

public func error<A>(x : String) -> A {
	assert(false, x)
}