3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php class Foo { protected $foo; public function __construct(Foo $foo = null) { if($foo == null) { $foo = new Foo($this); } $this->foo = $foo; } } $a = new Foo(); print_r($a);
Output for 5.1.0 - 5.6.23, 5.6.25 - 5.6.28, 7.0.0 - 7.0.8, 7.0.10 - 7.1.0
Foo Object ( [foo:protected] => Foo Object ( [foo:protected] => Foo Object *RECURSION* ) )
Output for 5.6.24, hhvm-3.12.0 - 3.13.2, 7.0.9

Process exited with code 137.
Output for hhvm-3.10.0
Foo Object ( [foo:protected] => Foo Object ( [foo:protected] => Foo Object ( [foo:protected] => Foo Object ( [foo:protected] => Array *RECURSION* ) ) ) )
Output for 5.0.0 - 5.0.5
Fatal error: Argument 1 must not be null in /in/Hh7TW on line 6
Process exited with code 255.
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected T_STRING, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /in/Hh7TW on line 5
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.4.1
Parse error: parse error, unexpected T_STRING, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /in/Hh7TW on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_OLD_FUNCTION' or `T_FUNCTION' or `T_VAR' or `'}'' in /in/Hh7TW on line 5
Process exited with code 255.