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<?php $data = []; $data['x'] = ['x_v']; $data['y'] = ['y_v']; $gen = new \ArrayIterator($data); var_dump($gen->valid()); var_dump($gen->current()); $filterFx = function ($row) { return count($row) !== false; // always true }; $genOrig = $gen; $gen = new \CallbackFilterIterator($gen, $filterFx); $genOrig->next(); // has correctly no effect // $gen->rewind(); // must be called, iterator is not initialized by default var_dump($gen->valid()); var_dump($gen->current()); var_dump($gen->valid()); var_dump($gen->next());
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
bool(true) array(1) { [0]=> string(3) "x_v" } bool(false) NULL bool(false) NULL

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