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<?php class Recursion implements JsonSerializable { public function __construct() { $this->cnt = 15; } public function jsonSerialize() { if ($this->cnt < 1) { return null; } $this->cnt--; return array($this->cnt => $this); } } var_dump(json_encode(new Recursion()));
Output for 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Deprecated: Return type of Recursion::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/HIv8Z on line 9 Deprecated: Creation of dynamic property Recursion::$cnt is deprecated in /in/HIv8Z on line 6 bool(false)
Output for 8.1.0 - 8.1.27
Deprecated: Return type of Recursion::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/HIv8Z on line 9 bool(false)
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.38, 7.0.0 - 7.0.33, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30
bool(false)
Output for 5.4.4 - 5.4.45
Warning: json_encode(): recursion detected in /in/HIv8Z on line 18 string(18) "{"14":{"13":null}}"
Output for 5.4.0 - 5.4.3
string(95) "{"14":{"13":{"12":{"11":{"10":{"9":{"8":{"7":{"6":{"5":{"4":{"3":{"2":{"1":[null]}}}}}}}}}}}}}}"
Output for 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Fatal error: Interface 'JsonSerializable' not found in /in/HIv8Z on line 3
Process exited with code 255.
Output for 5.0.0 - 5.0.4
Fatal error: Class 'JsonSerializable' not found in /in/HIv8Z on line 3
Process exited with code 255.
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected T_STRING, expecting '{' in /in/HIv8Z 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 T_STRING, expecting '{' in /in/HIv8Z on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `'{'' in /in/HIv8Z on line 3
Process exited with code 255.

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