Online PHP editor | output for SIlJo

Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6: Fatal error: Call to undefined function json_encode() in /in/SIlJo on line 3
Output for 4.4.5 - 4.4.9: Fatal error: Call to undefined function: json_encode() in /in/SIlJo on line 3
Output for 4.3.0 - 4.3.1, 4.3.2 - 4.3.11, 4.4.0 - 4.4.4: Fatal error: Call to undefined function: json_encode() in /in/SIlJo on line 3
Output for 5.2.0 - 5.2.17: Fatal error: Call to undefined function json_last_error() in /in/SIlJo on line 3
Output for 5.3.6 - 5.3.13, 5.3.15 - 5.3.29, 5.4.0 - 5.4.45: string(24) "{"foo":null,"bar":"bar"}" bool(true) Notice: Use of undefined constant JSON_PARTIAL_OUTPUT_ON_ERROR - assumed 'JSON_PARTIAL_OUTPUT_ON_ERROR' in /in/SIlJo on line 4 Warning: json_encode() expects parameter 2 to be long, string given in /in/SIlJo on line 4 NULL
Output for 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 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.34, 8.3.0 - 8.3.35, 8.4.1 - 8.4.26, 8.5.0 - 8.5.11: bool(false) bool(true) string(24) "{"foo":null,"bar":"bar"}"
Output for 5.3.14: Warning: json_encode(): Invalid UTF-8 sequence in argument in /in/SIlJo on line 3 bool(false) bool(true) Warning: json_encode(): Invalid UTF-8 sequence in argument in /in/SIlJo on line 4 string(24) "{"foo":null,"bar":"bar"}"
Output for 5.3.3 - 5.3.5: string(24) "{"foo":null,"bar":"bar"}" bool(false) Notice: Use of undefined constant JSON_PARTIAL_OUTPUT_ON_ERROR - assumed 'JSON_PARTIAL_OUTPUT_ON_ERROR' in /in/SIlJo on line 4 Warning: json_encode() expects parameter 2 to be long, string given in /in/SIlJo on line 4 NULL
Output for 5.3.0 - 5.3.2: Notice: Use of undefined constant JSON_ERROR_UTF8 - assumed 'JSON_ERROR_UTF8' in /in/SIlJo on line 3 string(24) "{"foo":null,"bar":"bar"}" bool(false) Notice: Use of undefined constant JSON_PARTIAL_OUTPUT_ON_ERROR - assumed 'JSON_PARTIAL_OUTPUT_ON_ERROR' in /in/SIlJo on line 4 Warning: json_encode() expects parameter 2 to be long, string given in /in/SIlJo on line 4 NULL