The mobx problem example

component.js

@inject('appStore') //different store
@observer
class VocalTest extends Component {

    constructor(props) {
        super(props);
        this.hearingTest = new Store(this.props.appStore.devices);
        this.prepareTest();
    }
  playNoise(valueToPlay) {
    //play to device
  }
  
  /* How can i acheive the following?
  * if hasChanged(valueToPlay) {
  *   playNoise(valueToPlay)
  * }
  */
  render() {...}
 }

Store.js

import { observable, action } from 'mobx';

class Store {
    definition = null;

    @observable settings;
    @observable device;
    //change to objects
    @observable loopIndex;
    @observable flowIndex;
    @observable canPlay;
    @observable canMark;
    @observable valueToPlay;
 /**
 * more data 
 */
}

autorun(() => {
  playNoise(this.hearingTest.valueToPlay); // reactively call it whenever the valueToPlay changes
});

is this similar to angular's $watch - if yes, bummer @benjamingr