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<?php var_dump(strtolower(0)); var_dump(strtolower(false)); var_dump(strtolower(true)); var_dump(strtolower(null));
Output for 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
string(1) "0" string(0) "" string(1) "1" Deprecated: strtolower(): Passing null to parameter #1 ($string) of type string is deprecated in /in/J7S66 on line 5 string(0) ""
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30
string(1) "0" string(0) "" string(1) "1" string(0) ""
preferences:
118.25 ms | 407 KiB | 5 Q