docs: function() {
      var tok = this.scan(/^\.(-?-?[_a-z][_a-z0-9\-]*)/i, 'class');
      if (tok) {
        this.tokens.push(tok);
        this.incrementColumn(tok.val.length);
        return true;
      }
      if (/^\.\-/i.test(this.input)) {
        this.error('INVALID_CLASS_NAME', 'If a class name begins with a "-" or "--", it must be followed by a letter or underscore.');
      }
      if (/^\.[0-9]/i.test(this.input)) {
        this.error('INVALID_CLASS_NAME', 'Class names must begin with "-", "_" or a letter.');
      }
      if (/^\./.test(this.input)) {
        this.error('INVALID_CLASS_NAME', '"' + /.[^ \t\(\#\.\:]*/.exec(this.input.substr(1))[0] + '" is not a valid class name.  Class names must begin with "-", "_" or a letter and can only contain "_", "-", a-z and 0-9.');
      }
    }