title: Is there a TypeScript equivalent to C#'s attributes
body: <p>In C# there is a syntax available to define attributes of a property.</p>
  
  <pre><code>[Required]
  string personName
  </code></pre>
  
  <p>It describes that personName is required. We can get the attributes of a property in any given time via reflection.</p>
  
  <p>I was wondering if TypeScript has some feature like that?</p>