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run code in 300+ PHP versions simultaneously
<?php class Foo implements JsonSerializable{ private $foo = 'bar'; private $baz = 'quux'; public function jsonSerialize(){ return ['foo'=>$this->foo, 'baz'=>$this->baz]; } } $arr = [new Foo(), new Foo(), new Foo()]; echo json_encode($arr);
Output for 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Deprecated: Return type of Foo::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/rTpXi on line 7 [{"foo":"bar","baz":"quux"},{"foo":"bar","baz":"quux"},{"foo":"bar","baz":"quux"}]
Output for 7.0.0 - 7.0.20, 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
[{"foo":"bar","baz":"quux"},{"foo":"bar","baz":"quux"},{"foo":"bar","baz":"quux"}]

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