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<?php $a = ' A0'; for ($i=0;$i<20;$i++) var_dump($a++);
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, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.32, 7.3.0 - 7.3.20, 7.4.0 - 7.4.8, 8.0.0alpha1 - beta1
string(3) " A0" string(3) " A1" string(3) " A2" string(3) " A3" string(3) " A4" string(3) " A5" string(3) " A6" string(3) " A7" string(3) " A8" string(3) " A9" string(3) " B0" string(3) " B1" string(3) " B2" string(3) " B3" string(3) " B4" string(3) " B5" string(3) " B6" string(3) " B7" string(3) " B8" string(3) " B9"