internal reflection on __serialize, __unserialize
internal reflection on __serialize, __unserialize

https://wiki.php.net/rfc/custom_object_serialization
https://github.com/peachpiecompiler/peachpie/issues/668

peachpiecompiler/peachpie,iolevel/peachpie,iolevel/peachpie,iolevel/peachpie-concept,peachpiecompiler/peachpie,iolevel/peachpie,peachpiecompiler/peachpie,iolevel/peachpie-concept,iolevel/peachpie-concept