typelevel
Pull#mapOutput deleted between 2.5.10 and 3.0.0
I'm trying to upgrade an application from fs2 2.5.10 to 3.2.5, and the method Pull#mapOutput has disappeared. It seems to have been deleted in this commit with no user-accessible replacement. As far as I can tell, there is no way to affect the output of a Pull without converting it to a Stream, but I can't do that yet because I still have results.
Is there some kind of migration guide from fs2 2-3? So far I have had to figure out migrations myself by diving through source code and reading github release notes (which do not mention the deletion of mapOutput).
Echoing some discussion on discord; this is due to how Pull's interpreter is written, mapOutput isn't polymorphic on returns, so this isn't a trivial change. It's possible but will require some work
Not being able to change the output type is very limiting when using Pull directly. There is flatMapOutput, but it's private to fs2.
For example, it's not possible to have Pull[F, A, B] and transform it to Pull[F, Either[A, B], Unit].
