title: Collapse comments and all functions in vim/gvim
body: <p>I'm a novice user to vim and I haven't been able to find in the internet how to collapse functions and I've figured out how to collapse the argument list in C with zfa} and zfa).  but I can't figure out how to collapse the comments sections. How do I do that?</p>
  
  <p>Second question but related, is there a way to collapse all functions/argument lists/comments in a file at the same time?</p>