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run code in 200+ php & hhvm versions
Bugs & Features
<?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);
based on GNqRb
Output for 5.6.0 - 5.6.30, hhvm-3.15.4, 7.0.0 - 7.3.0beta1
{ "string": "Hello!" }