title: Switching Antlr lexer modes from parser
body: <p>How to control switching <code>Antlr</code> lexer modes from parser actions?
  I extended the generated Parser and Lexer so I can call <code>pushMode</code> and <code>popMode</code> from parser witch in turn call suitable <code>pushMode</code> and <code>popMode</code> of lexer but with no effect. Is there any thing I can do to activate this functionality?</p>