code: function(mode, state, tabSize, ch) {
        var txt = this.text, stream = new StringStream(txt, tabSize);
        while (stream.pos < ch && !stream.eol()) {
          stream.start = stream.pos;
          var style = mode.token(stream, state);
        }
        return {start: stream.start,
                end: stream.pos,
                string: stream.current(),
                className: style || null,
                state: state};
      }
docs: Fetch the parser token for a given character. Useful for hacks that want to inspect the mode state (say, for completion).