title: Can the shunting yard algorithm parse POSIX regular expressions?
body: <p>At first glance, the <a href="http://en.wikipedia.org/wiki/Shunting_yard_algorithm" rel="noreferrer">shunting yard algorithm</a> seems applicable to POSIX regular expression parsing, but since I don't have much experience (or theoretical background) in writing parsers, I'd like to ask SO before jumping in and writing something only to get stuck halfway.</p>
  
  <p>Perhaps a more sophisticated version of the question is: What is a good formal statement of the class of problems the shunting yard algorithm can be applied to?</p>
  
  <p><strong>Clarification:</strong> This question is about whether you can parse POSIX re syntax into an abstract syntax tree using the basic principles of the shunting algorithm, not whether you can use regular expressions to implement the shunting algorithm. Sorry I wasn't clear enough stating that to begin with!</p>