JoelQ

Elm Types Glossary

There's a lot of type terminology and jargon going around when discussing types in Elm. This glossary attempts to list some of the most common type terms along with synonyms, terms from other language communities, examples, and links to more detailed articles on each topic.

• Custom Type
• Constructor
• Unit Type

jmitchell

let List/replicate = https://ipfs.io/ipfs/QmQ8w5PLcsNz56dMvRtq54vbuPe9cNnCCUXAQp6xLc6Ccx/Prelude/List/replicate in

let File = Natural in
let Rank = Natural in
let Square = { file : File, rank : Rank } in
let Move = { from : Square, to : Square } in

let Side = < white : {} | black : {} > in
let white = < white = {=} | black : {} > in
let black = < black = {=} | white : {} > in

rondy

FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.

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Effective Engineer - Notes

• By Edmond Lau
• Highly Recommended 👍
• http://www.theeffectiveengineer.com/

What's an Effective Engineer?

yang-wei

Should be work with 0.18

Destructuring(or pattern matching) is a way used to extract data from a data structure(tuple, list, record) that mirros the construction. Compare to other languages, Elm support much less destructuring but let's see what it got !

Tuple

myTuple = ("A", "B", "C")
myNestedTuple = ("A", "B", "C", ("X", "Y", "Z"))

chrisforrette

dependencies:
  cache_directories:
    - sassc
    - libsass
  post:
    - if [[ ! -e sassc ]]; then git clone git@github.com:sass/sassc.git sassc; fi
    - if [[ ! -e libsass ]]; then git clone --recursive git@github.com:sass/libsass.git && cd sassc && export SASS_LIBSASS_PATH=$(readlink -f ../libsass) && make && cd ..; fi
    - ln -s sassc/bin/sassc ~/bin/sassc 

pixeltrix

When should you use DateTime and when should you use Time?

It's a common misconception that [William Shakespeare][1] and [Miguel de Cervantes][2] died on the same day in history - so much so that UNESCO named April 23 as [World Book Day because of this fact][3]. However because England hadn't yet adopted [Gregorian Calendar Reform][4] (and wouldn't until [1752][5]) their deaths are actually 10 days apart. Since Ruby's Time class implements a [proleptic Gregorian calendar][6] and has no concept of calendar reform then there's no way to express this. This is where DateTime steps in:

>> shakespeare = DateTime.iso8601('1616-04-23', Date::ENGLAND)
=> Tue, 23 Apr 1616 00:00:00 +0000
>> cervantes = DateTime.iso8601('1616-04-23', Date::ITALY)
=> Sat, 23 Apr 1616 00:00:00 +0000

sebmarkbage

import { Component } from "React";

export var Enhance = ComposedComponent => class extends Component {
  constructor() {
    this.state = { data: null };
  }
  componentDidMount() {
    this.setState({ data: 'Hello' });
  }
  render() {

ericelliott

Essential JavaScript Links

I no longer mantain this list. There are lots of other very comprehensive JavaScript link lists out there. Please see those, instead (Google "awesome JavaScript" for a start).

samselikoff

This post is also on my blog, since Gist doesn't support @ notifications.

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Components are taking center stage in Ember 2.0. Here are some things you can do today to make the transition as smooth as possible:

• Use Ember CLI
• In general, replace views + controllers with components
• Only use controllers at the top-level for receiving data from the route, and use Ember.Controller instead of Ember.ArrayController or Ember.ObjectController
• Fetch data in your route, and set it as normal properties on your top-level controller. Export an Ember.Controller, otherwise a proxy will be generated. You can use Ember.RSVP.hash to simulate setting normal props on your controller.

evancz

Union Types

If Elm community is going to begin referring to "union types" instead of "algebraic data types" we should think about how that will work in practice. What discussions will we have? Will we find ourselves in awkward spots trying to explain things?

The following question/answer pairs simulate things I'd expect to see in a world of "union types". The pairs are grouped by what background I expect the questions to come from so we know the subtext. I have also added some meta comments in italic to explain my phrasing.

One thing to consider is that a lot of learners will not have a person to ask, so the path to arriving at these answers needs to be easy if you are just searching online.

General Questions