Explore Derivation Of Functional Abstractions

[adamgfraser]

No description provided.

[sideeffffect]

Good initiative 👍

[sideeffffect]

How come you don't need the derives Equal clauses? I though that you need to use them 🤔

https://docs.scala-lang.org/scala3/reference/contextual/derivation.html

[adamgfraser]

Apparently not.

[regiskuckaertz]

Suggested change

	inline given derived[A](using mirror: Mirror.Of[A]): Equal[A] =
	inline def derived[A](using mirror: Mirror.Of[A]): Equal[A] =

Otherwise it will derive for all types with no control right?

[adamgfraser]

given is in the documentation of this feature and using def creates an infinite loop in the derivation.

[sideeffffect]

That's what I've been alluding to in my comment above: #1079 (comment)

I also think that people would like to control it with derives Equal clauses.

[adamgfraser]

I opened an issue with the Scala 3 team regarding this.

[regiskuckaertz]

def creates an infinite loop in the derivation.

Erf that is ... weird. This code is equivalent to fully automatic derivation. With a def users would need to explicitly add the derives clause. I had many complaints with scanamo when instances were created implicitly.

I read the docs, the "recursively auto-derive" is an anti pattern imo, oh well I guess time will tell.

[sideeffffect]

So also according to @bishabosha we shouldn't put the given on the derived method to let the derivations be driven by derives clauses.

scala/scala3#16916

using def creates an infinite loop in the derivation

Are you able replicate it? Maybe we should report that.

I'm trying my lack with changing the official documentation scala/scala3#16919 Let's see where this leads 😄

[bishabosha]

given is in the documentation of this feature and using def creates an infinite loop in the derivation.

is the infinite loop with any type, or a specific example?

[adamgfraser]

The derivation for Color.