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const puppeteer = require('puppeteer');

(async () => {

    const browser = await puppeteer.launch();
    const page = await browser.newPage();
// Adjustments particular to this page to ensure we hit desktop breakpoint.
    page.setViewport({width: 1000, height: 600, deviceScaleFactor: 1});

    await page.goto('https://www.chromestatus.com/samples', {waitUntil: 'networkidle'});

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UPGRADE FROM 6.x to 7.0

Table of Contents

• babel
• babylon
• babel-core
• babel-preset-stage-3
• babel-plugin-syntax-class-constructor-call

kukiron

// get the average color of two hex colors.
function avgcolor(color1,color2){
    var avg  = function(a,b){ return (a+b)/2; },
        t16  = function(c){ return parseInt((''+c).replace('#',''),16) },
        hex  = function(c){ var t = (c>>0).toString(16);
                           return t.length == 2 ? t : '0' + t },
        hex1 = t16(color1),
        hex2 = t16(color2),
        r    = function(hex){ return hex >> 16 & 0xFF},
        g    = function(hex){ return hex >> 8 & 0xFF},

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/**
 * Simple authentication and authorization example with passport, node_acl,
 *  MongoDB and expressjs
 *
 * The example shown here uses local userdata and sessions to remember a
 *  logged in user. Roles are persistent all the way and applied to user
 *  after logging in.
 *
 * Usage:
 *  1. Start this as server

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// the main app file
import express from "express";
import loadDb from "./loadDb"; // dummy middleware to load db (sets request.db)
import authenticate from "./authentication"; // middleware for doing authentication
import permit from "./permission"; // middleware for checking if user's role is permitted to make request

const app = express(),
      api = express.Router();

// first middleware will setup db connection

kukiron

This article has been given a more permanent home on my blog. Also, since it was first written, the development of the Promises/A+ specification has made the original emphasis on Promises/A seem somewhat outdated.

You're Missing the Point of Promises

Promises are a software abstraction that makes working with asynchronous operations much more pleasant. In the most basic definition, your code will move from continuation-passing style:

getTweetsFor("domenic", function (err, results) {
 // the rest of your code goes here.

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// Async/Await requirements: Latest Chrome/FF browser or Babel: https://babeljs.io/docs/plugins/transform-async-to-generator/
// Fetch requirements: Latest Chrome/FF browser or Github fetch polyfill: https://github.com/github/fetch

// async function
async function fetchAsync () {
  // await response of fetch call
  let response = await fetch('https://api.github.com');
  // only proceed once promise is resolved
  let data = await response.json();
  // only proceed once second promise is resolved

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var db = mongoose.connect('mongodb://localhost:27017/DB'); 

// In middleware
app.use(function (req, res, next) {

  // action after response
  var afterResponse = function() {
   logger.info({req: req}, "End request");

    // any other clean ups

kukiron

import { Platform, ActionSheetIOS } from 'react-native';
import DocumentPicker from 'react-native-document-picker';
import ImagePicker from 'react-native-image-picker';
import RNFS from 'react-native-fs';

type Captions = {
  image: string,
  document: string,
  cancel: string,
  title: string,

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