(PHP 5 >= 5.1.0)
RecursiveCachingIterator::__construct — Construct
$iterator
[, string $flags = self::CALL_TOSTRING
] )
Constructs a new RecursiveCachingIterator,
which consists of a passed in iterator.
本函数还未编写文档，仅有参数列表。
iterator
The iterator being used.
flags
The flags. Use CALL_TOSTRING to call
RecursiveCachingIterator::__toString() for every element (the default),
and/or CATCH_GET_CHILD to catch exceptions when trying to get children.