docs: function (srcPath, options) {
          _.defaults(options || (options = {}), DEFAULT_OPTIONS);
          var separator = options.separator;
          var extname = path.extname(srcPath);
          var reg = new RegExp('^.+' + separator + '(.+)((' + separator + '.+)|(@\\d+x))\\' + extname + '$');
          if (extname === '.styl' || extname === '.css') {
              reg = new RegExp('^.+' + separator + '(.+)\\' + extname + '$');
          }
          var result = path.basename(srcPath).match(reg);
          return result && result[1];
      }