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<?php $input = [ 'firstName' => null, 'lastName' => null, 'category' => [ 'name' => null, 'service' => [ 'foo' => [ 'bar' => null ] ] ] ]; function prepareFields(array $array): array { return array_reduce(array_keys($array), function ($result, $key) use ($array) { $result[] = $key; if (is_array($array[$key])) { $result[$key] = prepareFields($array[$key]); } return $result; }); } print_r(prepareFields($input));
Output for 7.1.25 - 7.1.32, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.28, 8.4.1 - 8.4.14, 8.5.0 - 8.5.1
Array ( [0] => firstName [1] => lastName [2] => category [category] => Array ( [0] => name [1] => service [service] => Array ( [0] => foo [foo] => Array ( [0] => bar ) ) ) )
Output for 8.4.15
/bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.35' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.34' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15)
Process exited with code 1.
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