lourd

import { eventChannel } from 'redux-saga'
import { call, cps, take, fork, put, cancel, select } from 'redux-saga/effects'

function emitterChannel(emitter, eventType) {
  return eventChannel(emit => {
    emitter.on(eventType, emit)
    return () => emitter.off(eventType, emit)
  })
}

lourd

import React, { Component } from 'react'
import { withRouter } from 'react-router-dom'

@withRouter
class BeforeLocationChange extends Component {
  static propTypes = {
    history: PropTypes.shape({
      before: PropTypes.func.isRequired,
    }).isRequired,
    handler: PropTypes.func.isRequired,

lourd

class Foo {
  constructor() {
    this.feeling = '🤥'
  }
  
  speak() {
    console.log(this.feeling)
  }
}