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<?php function dot($array, $prepend = '') { $results = array(); foreach ($array as $key => $value) { if (is_array($value)) { $results = array_merge($results, dot($value, $prepend.$key.'.')); } else { if ($key === 'foo') print_r($value); $results[$prepend.$key] = $value; } } return $results; } $array = [ 'bar' => [ 'baz' => 1 ], 'foo' => [], ]; print_r(dot($array));

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