Антон

class User {
  get fullName() {
    return `${this.firstName} ${this.lastName}`;
  }
}

class User {
  constructor(age) {
    this.age = age;
  }

  onClick(event) {
    alert(this.age);
  }

// если используется babel, то
  onClick = event => {
    alert(this.age);
  }
}

let user = new User(24);
document.querySelector("#user2").addEventListener("click", user.onClick.bind(user));

import news from "./news.json";

// ...

<div classNews="news">
                {news.map((item, index) =>
                    <blockquote>
                        <h4>{item.title}</h4>
                        <p>{item.text}</p>
                    </blockquote>
                )}
            </div>
// ...

AppModal = reduxForm({
  form: 'AppForm',
  touchOnChange: true,
  
  enableReinitialize: true,
})(AppModal );

....
  this.run = function() {
  var self = this;
    setTimeout(function onReady() {
    self.doSomething();
  }, getTimeToBoil());
  };
.....

....
  this.run = function() {
    setTimeout(() => {
    this.doSomething();
  }, getTimeToBoil());
  };
.....