minimal evaluation

[Qian Xu]

> 
> if (isNull(foo) ||
>     isNull(foo.getBar) ||
>     isNull(foo.getBar.getBar2)
> {
>   return false;
> }

Update: If minimal evaluation is not always enabled, and foo.getBar is NULL.
I will get a segfault when evaluating foo.getBar.getBar2.