title: javascript and memoized getters
body: <p><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get" rel="noreferrer">This article describe getters</a>. It has a section "
  Smart / self-overwriting / lazy getters"
  And it's unclear for me, are getters 'memoized' by default or should I implement this feature by myself</p>
  
  <p>e.g. </p>
  
  <pre><code>class Foo() {
    get boo() {
      this._boo = this._boo || new Boo(); 
      return this._boo;  
    }
  }
  </code></pre>
  
  <p>or can I just write:</p>
  
  <pre><code>class Foo() {
    get boo() {
      return new Boo();  
    }
  }
  </code></pre>
  
  <p>to have the same result?</p>