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<?php $_POST = ['foo' => 'bar', 'foobar' => 123]; $validKeys = ['foo']; foreach ($validKeys as $key) { if (!isset($_POST['$key']) || !$_POST['$key']) { echo "$key: $val"; } // do stuff with $_POST[$key] }
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Warning: Undefined variable $val in /in/NYRbi on line 9 foo:
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.30, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined variable: val in /in/NYRbi on line 9 foo:
Output for 7.3.32 - 7.3.33
foo:
preferences:
264.44 ms | 401 KiB | 332 Q