I have a dilemma about library building that I&#39;m expect comes up for other people as well.<br><br>I&#39;m working on a library that includes a Cofunctor instance.&nbsp; I&#39;d love to import whatever standard module has the Cofunctor class, and maybe use some Cofunctor combinators.&nbsp; But, alas, I haven&#39;t found such a thing, and I&#39;m wondering what to do.&nbsp; If I keep my Cofunctor class in my own library, the generality does no good to me or anyone else.&nbsp; I certainly wouldn&#39;t expect someone to install my library just to get Cofunctor.&nbsp; Just as I wouldn&#39;t want a dependency on some other mostly-irrelevant library just to get Cofunctor.
<br><br>Another option is for me to make a tiny Cofunctor package with just a single class declaration, and make my library dependent on it.&nbsp; I guess that&#39;s the cleanest way and is what I&#39;m leaning toward.&nbsp; And maybe it could grow into a more useful Cofunctor library with the addition of functions on generic Cofunctor types.&nbsp; Does anyone have useful functionality to go into a Cofunctor module (beyond the class declaration)?
<br><br>Comments, advice, brainstorming most welcome.<br><br>&nbsp; Cheers,&nbsp; - Conal<br>