title: PEG and whitespace/comments
body: <p>I have some experience writing parsers with ANTLR and I am trying (for self-education :) ) to port one of them to PEG (Parsing Expression Grammar).</p>
  
  <p>As I am trying to get a feel for the idea, one thing strikes me as cumbersome, to the degree that I feel I have missed someting: How to deal with whitespace.</p>
  
  <p>In ANTLR, the normal way to deal with whitespace and comments were to put the tokens in a hidden channel, but with PEG grammars there is no tokenization step. Considering languages such as C or Java, where comments are allowed almost everywhere, one would like to "hide" the comments right away, but since the comments may have semantic meaning (for example when generating code documentation, class diagrams, etc), one would not just like to discard them.</p>
  
  <p>So, is there a way to deal with this?</p>