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run code in 300+ PHP versions simultaneously
<?php class SomeClass implements JsonSerializable { public function jsonSerialize() { return [get_object_vars($this)]; } } $class = new SomeClass; var_dump(json_encode($class)); var_dump(json_last_error() == JSON_ERROR_RECURSION); $arr = [$class]; var_dump(json_encode($arr)); var_dump(json_last_error() == JSON_ERROR_RECURSION); class SomeOtherClass implements JsonSerializable { public function jsonSerialize() { return get_object_vars($this); } } $class = new SomeOtherClass; var_dump(json_encode($class)); var_dump(json_last_error() == JSON_ERROR_RECURSION); $arr = [$class]; var_dump(json_encode($arr)); var_dump(json_last_error() == JSON_ERROR_RECURSION);
based on cZlaa
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.6 - 7.0.20, 7.1.0 - 7.1.33, 7.2.6 - 7.2.33, 7.3.0 - 7.3.26, 7.4.0 - 7.4.14, 8.0.0
string(4) "[[]]" bool(false) string(6) "[[[]]]" bool(false) string(2) "[]" bool(false) string(4) "[[]]" bool(false)
Output for 7.0.0 - 7.0.5
string(4) "[[]]" bool(false) bool(false) bool(true) string(2) "[]" bool(false) string(4) "[[]]" bool(false)