Note: the missing documentation of the argument list for this constructor is currently as follows (according to source code).
Param iter: see RecursiveIterator
Param mode:
- LEAVES_ONLY = (default) only iterate leaves
- SELF_FIRST = iterate parents prior to children
- CHILD_FIRST = iterate children prior to parents
Param flags:
- CATCH_GET_CHILD = ignore exceptions in getChildren() call