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<?php $a = '23bc'; $b = ''; $c = '123'; $cond1 = false; $cond2 = false; $test = array('a' => $a,'b' => $b, 'c' => $c); foreach ($test as $key => $str) { if( ($cond1 = strlen($str)== 0) || ($cond2 = ctype_digit($str)) ) { echo $key . ': Good to Go',"\n"; var_dump($cond1,$cond2); echo "\n"; } else { echo $key . ': Bad to Go',"\n"; var_dump($cond1,$cond2); echo "\n"; } }
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
a: Bad to Go bool(false) bool(false) b: Good to Go bool(true) bool(false) c: Good to Go bool(false) bool(true)

preferences:
247.92 ms | 406 KiB | 326 Q