Generic runtime representation

[tim2CF]

Hello! Is there some sort of generic runtime representation of protobuf types generated from protobuf files? Something similar to this (but for protobuf) https://hackage.haskell.org/package/aeson-1.5.3.0/docs/Data-Aeson.html#t:Value

[judah]

The Message instance is probably the closest thing to what you're asking. For each type we generate fieldsByTag and fieldsByName which let you walk through a proto value using type-safe reflection. You can look at proto-lens-arbitrary for an example how to use it:
http://hackage.haskell.org/package/proto-lens-arbitrary-0.1.2.9/docs/src/Data.ProtoLens.Arbitrary.html#arbitraryMessage

[tim2CF]

Thanks for reply, @judah !
I see, there is type-related information like this
http://hackage.haskell.org/package/proto-lens-arbitrary-0.1.2.9/docs/src/Data.ProtoLens.Arbitrary.html#arbitraryScalarValue
I mean Int32Field, Int64Field, UInt32Field etc. This is great, but this information is segregated from runtime values. Is there something similar to runtime AST (like in Aeson)? I want to recursively foldr real message with real values in generic way, and looking for something like

data ScalarValue = Int32Value Int32 | Int64Value Int64 | BytesValue ByteString | ... etc

And similar runtime AST for composite types