ZhihaoLau

const cors = require('cors')({origin: true});

exports.sample = functions.https.onRequest((req, res) => {
  cors(req, res, () => {
    res.send('Passed.');
  });
});

ZhihaoLau

function add1(v) { return v + 1; }
function isOdd(v) { return v % 2 == 1; }
function sum(total,v) { return total + v; }

var list = [2,5,8,11,14,17,20];

list
.map( add1 )
.filter( isOdd )
.reduce( sum );

ZhihaoLau

// A thing I want to do
// This flow only involves **one** promise, for example an ajax call
// None of the subsequent `then` or `catch` calls, return new promises.



var explode = false;
var promise = new Promise(function(resolve, reject) {
  if (explode) {

ZhihaoLau

// connect() is a function that injects Redux-related props into your component.
// You can inject data and callbacks that change that data by dispatching actions.
function connect(mapStateToProps, mapDispatchToProps) {
  // It lets us inject component as the last step so people can use it as a decorator.
  // Generally you don't need to worry about it.
  return function (WrappedComponent) {
    // It returns a component
    return class extends React.Component {
      render() {
        return (