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run code in 300+ PHP versions simultaneously
<?php $arr = array( 'key' => 'foo', 'key2' => 'bar', 0 => 'num_foo', 1 => 'num_bar' ); $new_array = array_filter ($arr, function($key) { return is_int($key); }, ARRAY_FILTER_USE_KEY); var_dump($new_array);

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