heygrady

Avoiding HOC; Favoring render props

The React community is moving away from HOC (higher order components) in favor of render prop components (RPC). For the most part, HOC and render prop components solve the same problem. However, render prop components provide are gaining popularity because they are more declarative and flexible than an HOC.

Read more:

• Use a render prop
• Breaking up with HOC
• HOC vs. render props
• React HOC docs
• React render props docs

paularmstrong

import hoistStatics from 'hoist-non-react-statics';
import React from 'react';

/**
 * Allows two animation frames to complete to allow other components to update
 * and re-render before mounting and rendering an expensive `WrappedComponent`.
 */
export default function deferComponentRender(WrappedComponent) {
  class DeferredRenderWrapper extends React.Component {
    constructor(props, context) {

pygy

The gist: by having a Promise adopt the state of a forever pending one, you can suspend its then handlers chain.

Promise.pending = Promise.race.bind(Promise, [])

let cancel

new Promise(function(fulfill, reject) {
  cancel = function() {fulfill(Promise.pending())}
  setTimeout(fulfill, 1000, 5)

markerikson

import React from "react";
import ReactDOM from "react-dom";

import configureStore from "./store/configureStore";


const store = configureStore();


const rootEl = document.getElementById("root");

jesstelford

Regular Event Loop

This shows the execution order given JavaScript's Call Stack, Event Loop, and any asynchronous APIs provided in the JS execution environment (in this example; Web APIs in a Browser environment)

---

Given the code

markerikson

[12:03 AM] acemarke: "controlled" and "uncontrolled" inputs
[12:04 AM] acemarke: if I have a plain, normal HTML page, and I put <input id="myTextbox" type="text" /> in my page(edited)
[12:04 AM] acemarke: and I start typing into that textbox
[12:04 AM] acemarke: it remembers what I've typed. The browser stores the current value for that input
[12:05 AM] acemarke: and then sometime later, I can get the actual element, say, const input = document.getElementById("myTextbox"), and I can ask it for its value: const currentText = input.value;
[12:05 AM] acemarke: good so far?
[12:08 AM] acemarke: I'll keep going, and let me know if you have questions
[12:08 AM] lozio: ok, actually I'm reading
[12:09 AM] lozio: good
[12:09 AM] acemarke: so, a normal HTML input field effectively stores its own value at all times, and you can get the element and ask for its value

antic183

// remove utf-8 BOM from ressource "res"
// res.charCodeAt(0) === 0xFEFF | res.charCodeAt(0) === 65279 
if (res.charCodeAt(0) === 0xFEFF) {
  res = res.substr(1);
}

jimfb

The unknown-prop warning will fire if you attempt to render a DOM element with a prop that is not recognized by React as a legal DOM attribute/property. You should ensure that your DOM elements do not have spurious props floating around.

There are a couple of likely reasons this warning could be appearing:

1. Are you using {...this.props} or cloneElement(element, this.props)? Your component is transferring its own props directly to a child element (eg. https://facebook.github.io/react/docs/transferring-props.html). When transferring props to a child component, you should ensure that you are not accidentally forwarding props that were intended to be interpreted by the parent component.

2. You are using a non-standard DOM attribute on a native DOM node, perhaps to represent custom data. If you are trying to attach custom data to a standard DOM element, consider using a custom data attribute (https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Using_data_attributes).

3. React does not yet reco

Williammer

function thunkify(fn) {
  return function() {
    var args = [].slice.call( arguments ),
        ctx = this;
        
    return function(cb) {
      var called;

      args.push(function(){
        if (called) return;

gaearon

function mapValues(obj, fn) {
  return Object.keys(obj).reduce((result, key) => {
    result[key] = fn(obj[key], key);
    return result;
  }, {});
}

function pick(obj, fn) {
  return Object.keys(obj).reduce((result, key) => {
    if (fn(obj[key])) {