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<?php $ll = new SplDoublyLinkedList(); $ll->push('one'); $ll->push('two'); $ll->push('three'); $ll->push('four'); $ll->rewind(); $iterations_done = iterator_apply($ll, function(Iterator $it) { echo $it->key(),"\t->", $it->current(),"\t->", ucfirst($it->current()),".\n"; $it->next(); return true; }, array($ll)); echo "Did iterate {$iterations_done} times \n";

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