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<?php $values = [ 'string-blank' => ' ', 'string-empty' => '', 'string-leading-zero' => '01', 'string-word' => 'foo', ]; var_dump(array_map(static function (string $value): bool { return ctype_digit($value); }, $values));
Output for 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
array(4) { ["string-blank"]=> bool(false) ["string-empty"]=> bool(false) ["string-leading-zero"]=> bool(true) ["string-word"]=> bool(false) }
preferences:
89.49 ms | 406 KiB | 5 Q