Jon Pretty

Silly question of the day: Is there a way in #scala3 to "unpack" a String at the type level ? ie: val x: Unpack["abc"] = ('a', 'b', 'c')

Yes, you can match on the type parameter's TypeRepr as a ConstantType(StringConstant(str)) and then just work on the string.

Ah I see. I can give it a try :) Any non-macro solution ?

For some reason I read the word "macro" in your question, but maybe that's what happens when you've been doing Scala 3 macros all day...

I don't know of one, though. But the macro is very easy. Something like this: def unpack[T <: Singleton & String: Type](using Quotes): Expr[List[Char]] = import quotes.reflect._ TypeRepr.of[T] match case ConstantType(StringConstant(str)) => '{ str.toList } (untested) ;)

Oh, and you'll also need the macro inline def unpack[T <: Singleton & String]: List[Char] = ${unpack[T]}