text: let secure = Symbol('private constructor');
  
  class Singleton {
  	constructor(token) {
  		if (secure !== token) {
  			throw new Error('Please use the getInstance() static method instead');
  		}
  	}
  
  	setText(text) {
  		this.text = text;
  	}
  
  	static getInstance() {
  		if (!Singleton.instance) {
  			Singleton.instance = new Singleton(secure);
  		}
  
  		return Singleton.instance;
  	}
  }
  
  export default Singleton;