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scalaupickle

Custom writer/reader in upickle no longer works after upgrade to 0.7.1


I have my own custom DateTime class for which I wrote the following custom writer and reader:

val dtWriter = Writer[DateTime]{
    case t => Js.Str(format(t))
}
val dtReader = Reader[DateTime]{
    case Js.Str(time) =>
        try {
            parse(time)
        }
        catch {
            case _: Exception =>
                SDateTime(0)
        }
}

However, I tried to upgrade my package version from 0.4.4 to 0.7.1 and this code no longer compiles giving me the following errors:

Error:(7, 8) object Js is not a member of package upickle

import upickle.Js

Error:(112, 23) object Writer does not take type parameters.

val dtWriter = Writer[DateTime]{

How should this be rewritten in the latest version of upickle?


Solution

  • Based just on reading http://www.lihaoyi.com/upickle/#CustomPicklers:

    val dtRW = readwriter[String].bimap[DateTime](
      t => format(t), // also `format _` or just `format` should work
      time =>
        try {
            parse(time)
        }
        catch {
            case _: Exception =>
                SDateTime(0)
        }
    )