title: What is for parser directive in docker
body: <p>I read <a href="https://docs.docker.com/engine/reference/builder/#parser-directives" rel="noreferrer">this link</a> which explains the valid directives. And it says "Parser directive is a special form of comment"</p>
  
  <p>I really don't understand what is the need for this and if it is comment, why docker parses it?</p>
  
  <p>I didn't find any good explanations related to this.</p>
  
  <p>Is it only escape directive? Because of windows path issues.</p>