gistfile1.txt

if (obj) {
    var levelOne = obj.levelOne;
    if (levelOne) {
      var levelTwo = levelOne.levelTwo;
      if (levelTwo) {
        var propertyValueOrUndefined = levelTwo.property;
        if (propertyValueOrUndefined)
          console.log(propertyValueOrUndefined);
      }
  
      var levelOneArray = levelOne.levelOneArray;
      if (levelOneArray && levelOneArray.length) {
        console.log(levelOneArray[0]);
      }
    }
  }