code: function (f) {
        var filename = path.basename(f);
        var extension = path.extname(f),
          allowedExtensions = lessWatchCompilerUtilsModule.config.allowedExtensions || defaultAllowedExtensions;
        if (filename.substr(0, 1) == '_' ||
          filename.substr(0, 1) == '.' ||
          filename == '' ||
          allowedExtensions.indexOf(extension) == -1
        )
          return true;
        else {
          return false;
        }
      }
docs: This is the function we use to filter the files to watch.