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<?php namespace Test; function callIsNull($arg) { return is_null($arg); } var_dump(is_null(null)); eval(' namespace Test; function is_null($arg) { return false; } '); var_dump(callIsNull(null));
Output for 5.5.0 - 5.5.36, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.7, 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
bool(true) bool(false)
Output for 7.1.10

Process exited with code 137.
preferences:
89.73 ms | 406 KiB | 5 Q