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<?php class StringValue implements JsonSerializable { public function __construct($string) { $this->string = (string) $string; } public function jsonSerialize() { return $this; } } echo json_encode(new StringValue('Hello!'), JSON_PRETTY_PRINT);
Output for 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Deprecated: Return type of StringValue::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/1WuTJ on line 8 Deprecated: Creation of dynamic property StringValue::$string is deprecated in /in/1WuTJ on line 5 { "string": "Hello!" }
Output for 8.1.0 - 8.1.28
Deprecated: Return type of StringValue::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/1WuTJ on line 8 { "string": "Hello!" }
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.6 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30
{ "string": "Hello!" }
preferences:
218.71 ms | 402 KiB | 163 Q