3v4l.org

run code in 300+ PHP versions simultaneously
<?php function f(?string $x, $y) {} // Ok. function g($x = NULL, $y) {} // Deprecated.
Output for 8.4.1 - 8.4.13
Deprecated: g(): Optional parameter $x declared before required parameter $y is implicitly treated as a required parameter in /in/qX4Ct on line 4
Output for 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26
Deprecated: Optional parameter $x declared before required parameter $y is implicitly treated as a required parameter in /in/qX4Ct on line 4
Output for 8.0.0 - 8.0.30
Deprecated: Required parameter $y follows optional parameter $x in /in/qX4Ct on line 4
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33
Parse error: syntax error, unexpected '?', expecting variable (T_VARIABLE) in /in/qX4Ct on line 3
Process exited with code 255.
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38
Parse error: syntax error, unexpected '?', expecting '&' or variable (T_VARIABLE) in /in/qX4Ct on line 3
Process exited with code 255.
Output for 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '?', expecting '&' or T_VARIABLE in /in/qX4Ct on line 3
Process exited with code 255.
Output for 5.0.0 - 5.0.5
Parse error: parse error, unexpected '?', expecting '&' or T_VARIABLE in /in/qX4Ct on line 3
Process exited with code 255.
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected '?', expecting ')' in /in/qX4Ct on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected '?', expecting ')' in /in/qX4Ct on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `')'' in /in/qX4Ct on line 3
Process exited with code 255.

preferences:
132.25 ms | 419 KiB | 5 Q