3v4l.org

run code in 300+ PHP versions simultaneously
<?php $result = json_encode(['end' => json_decode(null, true)]); var_dump($result); class A implements \JsonSerializable { function jsonSerialize() { return ['end' => json_decode(null, true)]; } } $a = new A(); $toJsonData = $a->jsonSerialize(); $result = json_encode($a); var_dump($result); $result = json_encode($toJsonData); var_dump($result);
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
Deprecated: json_decode(): Passing null to parameter #1 ($json) of type string is deprecated in /in/UraSC on line 3 string(12) "{"end":null}" Deprecated: Return type of A::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/UraSC on line 8 Deprecated: json_decode(): Passing null to parameter #1 ($json) of type string is deprecated in /in/UraSC on line 10 Deprecated: json_decode(): Passing null to parameter #1 ($json) of type string is deprecated in /in/UraSC on line 10 string(12) "{"end":null}" string(12) "{"end":null}"
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 Deprecated: json_decode(): Passing null to parameter #1 ($json) of type string is deprecated in /in/UraSC on line 3 string(12) "{"end":null}" Deprecated: Return type of A::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/UraSC on line 8 Deprecated: json_decode(): Passing null to parameter #1 ($json) of type string is deprecated in /in/UraSC on line 10 Deprecated: json_decode(): Passing null to parameter #1 ($json) of type string is deprecated in /in/UraSC on line 10 string(12) "{"end":null}" string(12) "{"end":null}"
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.7 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30
string(12) "{"end":null}" string(12) "{"end":null}" string(12) "{"end":null}"
Output for 7.0.0 - 7.0.6
string(12) "{"end":null}" bool(false) string(12) "{"end":null}"
preferences:
293.57 ms | 401 KiB | 336 Q