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Cannot create anonymous given Codec in Scala3

See original GitHub issue

import com.github.plokhotnyuk.jsoniter_scala.core.*
import com.github.plokhotnyuk.jsoniter_scala.macros.JsonCodecMaker.*

case class DeResult[T](isSucceed: Boolean, data: T, message: String)
case class RootPathFiles(files: List[String])

given JsonValueCodec[DeResult[Option[String]]] = make
given JsonValueCodec[DeResult[RootPathFiles]]  = make

Naming Error: xxx\endpoints\TestEndpoint.scala:16:8 
[error] 16 |  given JsonValueCodec[DeResult[RootPathFiles]]  = make
[error]    |        ^
[error]    |Double definition:
[error]    |final lazy given val given_JsonValueCodec_DeResult:
[error]    |  com.github.plokhotnyuk.jsoniter_scala.core.JsonValueCodec[
[error]    |    de.video.test.model.DeResult[Option[String]]
[error]    |  ] in object TestEndpoint at line 15 and
[error]    |final lazy given val given_JsonValueCodec_DeResult:
[error]    |  com.github.plokhotnyuk.jsoniter_scala.core.JsonValueCodec[
[error]    |    de.video.test.model.DeResult[de.video.test.model.RootPathFiles]
[error]    |  ] in object TestEndpoint at line 16

Sine the same case class with different type parameters, jsoniter use the same given var name.

A workaround is

given jsonValueCodecImplicit1: JsonValueCodec[DeResult[Option[String]]] = make
given jsonValueCodecImplicit2: JsonValueCodec[DeResult[RootPathFiles]]  = make

Issue Analytics

State:
Created a year ago
Comments:5 (5 by maintainers)

Top GitHub Comments

1reaction

djx314commented, Jun 20, 2022

Yes, it’s the same problem. Now use

import com.github.plokhotnyuk.jsoniter_scala.core.*
import com.github.plokhotnyuk.jsoniter_scala.macros.JsonCodecMaker.*
import de.video.test.model.*

trait JsonCodec:

  private type DeAlias1 = DeResult[Option[String]]
  private type DeAlias2 = DeResult[RootPathFiles]
  private type DeAlias3 = List[String]
  private type DeAlias4 = RootFileNameRequest
  private type DeAlias5 = DirId

  given JsonValueCodec[DeAlias1] = make
  given JsonValueCodec[DeAlias2] = make
  given JsonValueCodec[DeAlias3] = make
  given JsonValueCodec[DeAlias4] = make
  given JsonValueCodec[DeAlias5] = make

end JsonCodec

object JsonCodec extends JsonCodec

and

import de.video.test.cases.model.JsonCodec.given

It’s more suitable for jsoniter’s style since that jsoniter not support nested Codec count.

0reactions

djx314commented, Jun 20, 2022

I see. Usually, when I need a Encoder[DeResult[List[Model1]]], actually I just need Encoder[DeResult[T]], Encoder[List[T]] and Encoder[Model1]. It does not seem to be a urgent issue in Scala3.