I have a dilemma about library building that I'm expect comes up for other
people as well.
I'm working on a library that includes a Cofunctor instance. I'd love to
import whatever standard module has the Cofunctor class, and maybe use some
Cofunctor combinators. But, alas, I haven't found such a thing, and I'm
wondering what to do. If I keep my Cofunctor class in my own library, the
generality does no good to me or anyone else. I certainly wouldn't expect
someone to install my library just to get Cofunctor. Just as I wouldn't
want a dependency on some other mostly-irrelevant library just to get
Cofunctor.
Another option is for me to make a tiny Cofunctor package with just a single
class declaration, and make my library dependent on it. I guess that's the
cleanest way and is what I'm leaning toward. And maybe it could grow into a
more useful Cofunctor library with the addition of functions on generic
Cofunctor types. Does anyone have useful functionality to go into a
Cofunctor module (beyond the class declaration)?
Comments, advice, brainstorming most welcome.
Cheers, - Conal
