given: sealed trait Data final case class Foo() extends Data final case class Bar() extends Data final case class TimestampedData[A <: Data](data: A, timestamp: Long) Is there a succint way to...

Is there a clean way to access the default values of a case class fields when performing type class derivation in Scala 3 using Mirrors? For example: case class Foo(s: String = "bar", i: ...

I want to define equality for some type that can be part of other objects or collections using cats/kitten. I don't want to have to define the equality for every other class. For example: import ca...

Suppose I've got an ADT like this: sealed trait Event case class Foo(i: Int) extends Event case class Bar(s: String) extends Event case class Baz(c: Char) extends Event case class Qux(values: Lis...

Suppose I've been working with some JSON like this: { "id": 123, "name": "aubergine" } By decoding it into a Scala case class like this: case class Item(id: Long, name: String) This works jus...

Suppose I have a ADT in Scala: sealed trait Base case class Foo(i: Int) extends Base case class Baz(x: String) extends Base I want to encode values of this type into the JSON that looks like th...

I'm paraphrasing a question from the circe Gitter channel here. Suppose I've got a Scala sealed trait hierarchy (or ADT) like this: sealed trait Item case class Cake(flavor: String, height: Int) ...