code: function() {
      var captures;
      if (captures = /^("[^"]*"|'[^']*')[ \t]*/.exec(this.str)) {
        var str = captures[1]
          , quote = captures[0][0];
        this.skip(captures);
        str = str.slice(1,-1).replace(/\\n/g, '\n');
        return new Token('string', new nodes.String(str, quote));
      }
    }
docs: '"' [^"]+ '"' | "'"" [^']+ "'"