code: function serializeObject(obj) {
    var seen = [];
  
    return JSON.stringify(obj, function(key, val) {
      val = toJsonReplacer(key, val);
      if (isObject(val)) {
  
        if (seen.indexOf(val) >= 0) return '...';
  
        seen.push(val);
      }
      return val;
    });
  }
docs: /* global: toDebugString: true