title: How do I dynamically assign properties
body: <p>Having object like this </p>
  
  <pre><code>var obj = {};
  obj.prop1 = "value1";
  obj.prop2 = "value2";
  </code></pre>
  
  <p>and string </p>
  
  <pre><code>var propName = "prop1"
  </code></pre>
  
  <p>how can I update correct property of name under propName like this</p>
  
  <pre><code>obj.{propName} = someValue
  </code></pre>