title: Is there a Vim equivalent to the Linux/Unix "fold" command?
body: <p>I realize there's a way in Vim to hide/fold lines, but what I'm looking for is a way to select a block of text and have Vim wrap lines at or near column 80.  </p>
  
  <p>Mostly I want to use this on comments in situations where I'm adding some text to an existing comment that pushes it over 80 characters.  It would also be nice if it could insert the comment marker at the beginning of the line when it wraps too.  Also I'd prefer the solution to not autowrap the entire file since I have a particular convention that I use when it comes to keeping my structured code under the 80 character line-length.  </p>
  
  <p>This is mostly for Python code, but I'm also interested in learning the general solution to the problem in case I have to apply it to other types of text.</p>