emilong

const moment = require('moment');
const PERIOD = moment.duration(3, 'days');

module.exports = {
  PERIOD,
  
  isWithinPeriod(test) {
    return moment().add(PERIOD).isAfter(test);
  },
};

emilong

#!/usr/bin/env node

// skip the first two args as they are node and this script
const [,,filepath] = process.argv;

doSomethingFSLike(filepath);

emilong

const {
  topLevel: {
    intermediate,    // declaration of intermediate
    intermediate: {
      nested         // declaration of nested
    }
  }
} = {
  topLevel: {
    intermediate: {

emilong

function defaults({ a = 1, b = 2 } = {}) {
  console.log('a', a); 
  console.log('b', b);
}

defaults();
// a 1
// b 2

defaults({ a: 42, b: 32 });

emilong

function defaults({ a, b } = { a: 1, b: 2 }) {
  console.log('a', a); 
  console.log('b', b);
}

defaults();
// a 1
// b 2

defaults({ a: 42, b: 32 });

emilong

// simple renaming to avoid collisions or just as a preference.
const a = 5;
const { a: b } = { a: 3 };

console.log(b); // prints 3

// rename for another API and use enhanced object literal notation.
function verifyUser({ userId: id }) {
  return User.update({ id, verified: true });
}

emilong

// can destructure arrays
const [a, b] = [1,2]; // a = 1, b = 2

// can destructure object keys
const { a } = { a: 3 }; // a = 3

// even function parameters
function foo({ a }) {
  console.log(a);
}

emilong

import React, { Component } from 'react'
import { SubWidgetLink } from './routes'

export default class MyComponentWithALink extends Component {
  render() {
    const { widget } = this.props

    return (
      <div>
        ...

emilong

import { combineReducers } from 'redux'
import { createAction, handleActions } from 'redux-actions'

const authorFetched = createAction('AUTHOR_FETCHED')
const bookFetched   = createAction('BOOK_FETCHED')

const authorReducer = handleActions({
  AUTHOR_FETCHED: (state, action) => {
    const author = action.payload

emilong

import { combineReducers } from 'redux'
import { createAction, handleActions } from 'redux-actions'

const authorFetched = createAction('AUTHOR_FETCHED')
const bookFetched   = createAction('BOOK_FETCHED')

const literaryReducer = handleActions({
  // maybe an author has a bunch of books as sub-resources
  AUTHOR_FETCHED: (state, action) => {
    const author = action.payload