3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arrayIterator = new ArrayIterator(array('key 1' => 'value 1', 'key 2' => array('value 2'))); $regexIterator = new RegexIterator($arrayIterator, '/^key/', RegexIterator::MATCH, RegexIterator::USE_KEY); foreach ($regexIterator as $key => $value) { var_dump($key, $value); }

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