reillyeon

When does an async function return?

Someone recently asked me when an async function in JavaScript "returns". This is an interesting question because while a function like f() below has a return statement in it, f() actually returns much earlier than that. To understand how this works, let's take a look at an example function. Here, a() and c() are normal synchronous functions and b() is another asynchronous function.

async function f() {
  a();
  await b();
  return c();
}

highercomve

const compose = (fn, ...funcs) => {
  return (...args) => {
    return funcs.reduce((acc, func) => func(acc), fn(...args))
  }
}

const generate = (fn, dependency = LazyIterable, descriptor) => {
  return Object.create(
    Object.assign({ [Symbol.iterator]: fn }, dependency),
    descriptor

dungdm93

variables:
  ANDROID_COMPILE_SDK: "28"

test:unit:
  image: circleci/android:api-${ANDROID_COMPILE_SDK}
  cache:
    key: gradle-cache
    paths: [ .gradle ]
  variables:
    # GRADLE_OPTS: "-Dorg.gradle.daemon=false"

NigelEarle

Migrations & Seeding

What are migrations??

Migrations are a way to make database changes or updates, like creating or dropping tables, as well as updating a table with new columns with constraints via generated scripts. We can build these scripts via the command line using knex command line tool.

To learn more about migrations, check out this article on the different types of database migrations!

Creating/Dropping Tables

ncochard

When you create a npm package, remember it might be used in a browser or a server, or even a command line utility… For each package you create, please pay attention at what it will be used for:

1. Is it going to be used as a dependency to a nodejs application that is not bundled? (e.g. command line utilities)
2. Is it going to be used as a dependency to a nodejs application that is bundled? (e.g. AWS Lambdas)
3. Is it going to be used as a dependency to a browser application (always bundled)?.

• In cases 2) and 3) you want to allow for tree shaking.
• In cases 1) and 2) you want to benefit from the "ES6"/"ES next" features supported natively by nodejs.
• In case 3) you also want to benefit from the native support of "ES6" from your browser.

juhamust

README

This gist was created after spending too much time figuring out how to setup serverless authentication using AWS Cognito and Facebook login. Hope you find it useful!

DISCLAIMER: I have not re-tested the steps but wrote them afterwards. Therefore, it is very likely to contain some issues.

Steps

clemlatz

# SSL server config
server {
        listen 443 ssl;

        server_name secure.example.com;

        ssl_certificate /etc/letsencrypt/live/secure.example.com/fullchain.pem;
        ssl_certificate_key /etc/letsencrypt/live/secure.example.com/privkey.pem;
        
        ssl_protocols TLSv1 TLSv1.1 TLSv1.2;

sebmarkbage

import { Component } from "React";

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

sebmarkbage

var Bar1 = base => class extends base {
  componentWillMount(){
    super.componentWillMount();
    console.log('Bar1');
  }
};

var Bar2 = base => class extends base {
  componentWillMount(){
    super.componentWillMount();

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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