ivanberry

Install MongoDB with Homebrew

brew install mongodb
mkdir -p /data/db

Set permissions for the data directory

Ensure that user account running mongod has correct permissions for the directory:

ivanberry

Understanding closures, callbacks and promises

For a code newbie like myself, callbacks, closures and promises are scary JavaScript concepts.

10 months into my full-time dev career, and I would struggle to explain these words to a peer.

So I decided it was time to face my fears, and try to get my head around each concept.

Here are the notes from my initial reading. I'll continue to refine them as my understanding improves.

ivanberry

// 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 (

ivanberry

Make a basic template render function

Given:

var str = '{{name}}is cool, and he is only {{age}} years old!';
var context = {
  name: 'ivanberry',
  age: 20
}

ivanberry

100 Stupid Questions for React Native

What is React Native? Is it same as React?

React Native lets you build mobile apps using only JavaScript. It uses the same design as React, letting you compose a rich mobile UI from declarative components.

https://facebook.github.io/react-native/

Is React Native easy to learn?

It depends on what project you are going to build. As for front-end developer, you nearly need to learn nothing, only a new way to write javascript (Redux, JSX).

Do I must learn Redux?

ivanberry

function interval(duration, fn){
  this.baseline = undefined
  
  this.run = function(){
    if(this.baseline === undefined){
      this.baseline = new Date().getTime()
    }
    fn()
    var end = new Date().getTime()
    this.baseline += duration

ivanberry

`emacs --daemon` to run in the background.
`emacsclient.emacs24 <filename/dirname>` to open in terminal

NOTE: "M-m and SPC can be used interchangeably".

* Undo - `C-/`
* Redo - `C-?`
* Change case: 1. Camel Case : `M-c`
               2. Upper Case : `M-u`
               3. Lower Case : `M-l`

ivanberry

# 建议：官方文档对每个规则有简单易懂的例子说明，有时间的同学可以查阅一遍。
# 官方文档 http://eslint.org/docs/rules/

extends: 'eslint:recommended'

# 规则按照首字母在字母表升序排序
rules:

  # 单行代码块大括号后需要一个空格
  block-spacing: 2

ivanberry

// Simple JavaScript Templating
// John Resig - http://ejohn.org/ - MIT Licensed
(function(){
    var cache = {};

    this.tmpl = function tmpl(str, data){
    // Figure out if we're getting a template, or if we need to
    // load the template - and be sure to cache the result.
    var fn = !/\W/.test(str) ?
        cache[str] = cache[str] ||

ivanberry

```html
<fieldset class="rating">
    <legend>Please rate:</legend>
    <input type="radio" id="star5" name="rating" value="5" />
    <label for="star5" title="Rocks!">5 stars</label>
    <input type="radio" id="star4" name="rating" value="4" />
    <label for="star4" title="Pretty good">4 stars</label>
    <input type="radio" id="star3" name="rating" value="3" />
    <label for="star3" title="Meh">3 stars</label>
    <input type="radio" id="star2" name="rating" value="2" />