title: Problems with context in js
body: <p>I have decided to exercise in js and code call function. Nevertheless, I got stuck with <code>"undefined undefined"</code> output.
  Here is the code:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>var alex = {
    name: "alex",
    surname: "surname",
  }
  let nameyourself = function() {
    console.log(`${this.name} ${this.surname}`);
  }
  
  
  Function.prototype.calling = function(smth) {
    smth.__proto__.calledfunct = this;
    return smth.__proto__.calledfunct();
  }
  nameyourself.calling(alex);</code></pre>
  </div>
  </div>
  </p>
  
  <p>But when I delete <code>.__proto__</code>, everything works fine. I suppose that the function doesn't get the context of <code>alex</code>.</p>