welll

import express from 'express';
import React from 'react';
import { renderToString } from 'react-dom/server';

const app = express();

class ErrorBoundary extends React.Component {
  constructor(props) {
    super(props);
    this.state = { hasError: false };

welll

// Found on: http://hints.macworld.com/article.php?story=2008051406323031

// File: 
// click.m
//
// Compile with: 
// gcc -o click click.m -framework ApplicationServices -framework Foundation
//
// Usage:
// ./click -x pixels -y pixels 

welll

#!/bin/sh

set -e

PACKAGE_JSON="package.json"
PACKAGE_JSON_NEW="package.new.json"
PACKAGE_LOCK="package-lock.json"  # default. when shrinkwrap used, is npm-shrinkwrap.json

function usage() {
	echo "Usage: ${0} -d=<abs-path-to-dir-with-package.json> [-lf=<name-of-the-lock-file>]"

welll

let myAsyncFunctionThatReturnsPromise = new Promise((resolve, reject) => {
  setTimeout(function(){
    resolve("Success!")
  }, 2500)
  
})

let foo1 = Promise.resolve()
     .then(function(){  callUndefinedFunction() })
     .catch((e)=> console.log(`Error: ${e}`))

welll

#!/usr/bin/env python3

import BaseHTTPServer, SimpleHTTPServer
import urlparse
import ssl

# update these vars
cert='/path-to-cert.pem'
key='/path-to-private-key.pem'
bindHost='0.0.0.0'

welll

Update May 2017

Eric Bidelman has documented some of the common workflows possible with headless Chrome over in https://developers.google.com/web/updates/2017/04/headless-chrome.

Update

If you're looking at this in 2016 and beyond, I strongly recommend investigating real headless Chrome: https://chromium.googlesource.com/chromium/src/+/lkgr/headless/README.md

Windows and Mac users might find using Justin Ribeiro's Docker setup useful here while full support for these platforms is being worked out.

welll

node debug $(which gulp) taskName

welll

global.myNumber = 5; //Global variable initialized to value 5. 

welll

function checkIfImageExist(src, cb) {

    var img = new Image();

    img.onload = function() {
        cb(null)
    }

    img.onerror = function(e) {

welll

/* missing a RETURN statement */

fs.readFile(`${filePath}`, (err, data) => {
  if (err) {
     console.log(`Error reading file: ${filePath}`) 
  }
  
  //...
  //code
  //...