Add support for the Newtype library

[gvolpe]

It seems the @newtype annotation from the scala-newtype library doesn't work well with the @derive annotation.

This fails to compile:

@newtype
@derive(show)
case class Foo(value: String)

@newtype
@derive(show)
case class Bar(value: Int)

@derive(show)
final case class Ctx(foo: Foo, bar: Bar)

Here's the error:

[error] /examples/foo.scala:19:4: magnolia: could not find Show.Typeclass for type examples..Foo
[error]     in parameter 'foo' of product type examples.Ctx
[error]   @derive(show)
[error]    ^
[error] one error found
[error] (Compile / compileIncremental) Compilation failed

Maybe worth looking into scalaz-deriving that has support for it.

[REDNBLACK]

I’m currently in progress of making them (derevo + newtype) to work together nicely. Soon (tm)

[gvolpe]

Awesome! Thanks for your blazing fast response 😄

Should I close this issue or you want me to leave it open until this happens? :)

[gvolpe]

FWIW derevo will be featured in Chapter 10 of my book https://leanpub.com/pfp-scala 🤓

[REDNBLACK]

Leave it open. btw, nice book, bought it as soon as it came :)

[gvolpe]

Glad to hear, thanks! :)

[rabzu]

Hi, any news on this?