Why must I rewind IteratorIterator

Question

$arrayIter = new ArrayIterator( array(1, 2) );
$iterIter = new IteratorIterator($arrayIter);

var_dump($iterIter->valid()); //false
var_dump($arrayIter->valid(         


        

Answer 1

Like @johannes said, the position isn't initialized in the IteratorIterator and thus it is not valid before any other of it's methods are run on it or it is used with foreach()

Try to do

var_dump( $iterIter->current() ); // NULL
var_dump( $iterIter->getInnerIterator()->current() ); // 1

And also

$iterIter->rewind();
var_dump( $iterIter->current() ); // 1
var_dump( $iterIter->getInnerIterator()->->current() );  // 1

And also note that on an unitiliazed IteratorIterator:

$iterIter->next(); // 2
var_dump( $iterIter->current()) ; // 2 (from NULL to 2)
var_dump( $iterIter->getInnerIterator()->current() );  // 2

Note that $arrayIter from your code snippet is identical to $iterIter->getInnerIterator().

Hope that shed some light.