text: function match(haystack, filter) {
      if (!filter) {
          return true;
      }
  
      return Object.keys(filter).every(function(key) {
          var val = filter[key];
          if (val instanceof Object) {
              return match(haystack[key], val);
          }
          return filter[key] === haystack[key];
      });
  };
  
  module.exports = match;
  