@dave08 I mean parse once, just to detect which of them is not null, then parse again as error/result

Measure.

But overall, I wouldn't worry too much, these extra JSON payloads are usually not that big

but you can probably get fancy with the streaming API if you want to avoid overhead

read each field as it comes, wait for the type one, then you know how to parse the string when it comes in

My payloads are requests that could potentially retrieve an array of lots of objects... it might be nice to avoid the extra step. The streaming doesn't help, since my JsonRpc client is seperate from the one actually parsing the payloads...

So I won't know the type yet...

So so far it's either using JsonValue type for

result

...?