On Thursday, 13 October 2022 at 19:00:30 UTC, Sergey wrote:
I'm not a professional of IEEE 754, but just found this behavior at rounding in comparison with other languages. I supose it happened because in D float numbers parsed as double and have a full length of double while rounding. But this is just doesn't match with behavior in other languages.
So there is no luck with std.json for me. But when std is not the solution, third party libraries could help. I've tried ASDF. This is kind of archived library, but it works well, its documentation is small and clear (mir-ion really needs to improve documentation).
So in asdf we could just serialize the json and it will automatically round numbers with the same **magic** logic for floating as other languages do.
The only thing: some numbers which are usually double could be presented in JSON as integers. Automatically asdf convert them to double too. In case you need to process them exactly as integers you could use Variant!(int, double) as a type of the data. And provide your custom serializer/deserializer as it is proposed in asdf documentation example.
http://asdf.libmir.org/asdf_serialization.html#.serializeToAsdf PS Thanks to Steven for his suggestions in Discord.
