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<?php var_dump(json_encode("\xB1\x31")); echo json_last_error();
Output for 5.3.1 - 5.3.13, 5.3.15 - 5.4.32, hhvm-3.0.1 - 3.2.0
string(4) "null" 5
Output for 5.5.0 - 5.6.0, php7@20140507 - 20140901
bool(false) 5
Output for 5.3.14
Warning: json_encode(): Invalid UTF-8 sequence in argument in /in/hPEGA on line 3 bool(false) 5
Output for 5.3.0
string(4) "null" 0
Output for 5.2.7 - 5.2.17
string(4) "null" Fatal error: Call to undefined function json_last_error() in /in/hPEGA on line 4
Process exited with code 255.
Output for 5.2.0 - 5.2.6
string(2) """" Fatal error: Call to undefined function json_last_error() in /in/hPEGA on line 4
Process exited with code 255.
Output for 5.0.0 - 5.1.6
Fatal error: Call to undefined function json_encode() in /in/hPEGA on line 3
Process exited with code 255.
Output for 4.4.5 - 4.4.9
Fatal error: Call to undefined function: json_encode() in /in/hPEGA on line 3
Process exited with code 255.
Output for 4.3.2 - 4.4.4
Fatal error: Call to undefined function: json_encode() in /in/hPEGA on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1
Fatal error: Call to undefined function: json_encode() in /in/hPEGA on line 3