swannodette

Code Splitting

NOTE: This gist uses the master branch of ClojureScript. Clone ClojureScript and from the checkout run ./script/bootstrap and ./script/uberjar. This will produce target/cljs.jar which you can use to follow this guide.

As client applications become larger it becomes desirable to load only the code actually required to run a particular logical screen. Previously ClojureScript :modules compiler option permitted such code splitting, but this feature only worked under :advanced compilation and users would still have to manage loading these splits. :modules also required manual

reborg

Rich Already Answered That!

A list of commonly asked questions, design decisions, reasons why Clojure is the way it is as they were answered directly by Rich (even when from many years ago, those answers are pretty much valid today!). Feel free to point friends and colleagues here next time they ask (again). Answers are pasted verbatim (I've made small adjustments for readibility, but never changed a sentence) from mailing lists, articles, chats.

How to use:

• The link in the table of content jumps at the copy of the answer on this page.
• The link on the answer itself points back at the original post.

Table of Content

orther

import R from 'ramda';
const items = [
  {id: 1, name: 'Al',       country: 'AA'},
  {id: 2, name: 'Connie',   country: 'BB'},
  {id: 3, name: 'Doug',     country: 'CC'},
  {id: 4, name: 'Zen',      country: 'BB'},
  {id: 5, name: 'DatGGboi', country: 'AA'},
  {id: 6, name: 'Connie',   country: 'AA'},
];

bvaughn

React lifecycle cheatsheet

Method	Side effects1	State updates2	Example uses
Mounting
componentWillMount		✓	Constructor equivalent for createClass
render			Create and return element(s)
componentDidMount	✓	✓	DOM manipulations, network requests, etc.
Updating
componentWillReceiveProps		✓	Update state based on changed props

bmhatfield

# If you use bash, this technique isn't really zsh specific. Adapt as needed.
source ~/keychain-environment-variables.sh

# AWS configuration example, after doing:
# $  set-keychain-environment-variable AWS_ACCESS_KEY_ID
#       provide: "AKIAYOURACCESSKEY"
# $  set-keychain-environment-variable AWS_SECRET_ACCESS_KEY
#       provide: "j1/yoursupersecret/password"
export AWS_ACCESS_KEY_ID=$(keychain-environment-variable AWS_ACCESS_KEY_ID);
export AWS_SECRET_ACCESS_KEY=$(keychain-environment-variable AWS_SECRET_ACCESS_KEY);

hallettj

/* @flow */

// Helper function for matching against an ADT.
export function match<A,B>(matcher: A): (match: (matcher: A) => B) => B {
  return match => match(matcher)
}

developit

/** Async version of Array.prototype.reduce()
 *  await reduce(['/foo', '/bar', '/baz'], async (acc, v) => {
 *    acc[v] = await (await fetch(v)).json();
 *    return acc;
 *  }, {});
 */
export async function reduce(arr, fn, val, pure) {
  for (let i=0; i<arr.length; i++) {
    let v = await fn(val, arr[i], i, arr);
    if (pure!==false) val = v;

juanmaguitar

// https://medium.com/@rdsubhas/es6-from-callbacks-to-promises-to-generators-87f1c0cd8f2e#.q7boouq4o

/* Step 1: Callback hell — N levels deep */

var request = require('request');
var url1='http://httpbin.org/', url2=url1, url3=url1, url4=url1;

function foo(finalCallback) {
  request.get(url1, function(err1, res1) {
    if (err1) { return finalCallback(err1); }

acdlite

// getComponent is a function that returns a promise for a component
// It will not be called until the first mount
function asyncComponent(getComponent) {
  return class AsyncComponent extends React.Component {
    static Component = null;
    state = { Component: AsyncComponent.Component };

    componentWillMount() {
      if (!this.state.Component) {
        getComponent().then(Component => {

jdegoes

Applied Functional Programming with Scala - Notes

Copyright © 2016-2018 Fantasyland Institute of Learning. All rights reserved.

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x