On 8 May 2012, at 21:42, Felipe Almeida Lessa wrote: > On Tue, May 8, 2012 at 2:36 PM, MigMit <miguelim...@yandex.ru> wrote: >> Hi café, a quick question. >> >> Is there a somewhat standard class like this: >> >> class Something c where >> unit :: c () () >> pair :: c x y -> c u v -> c (x, u) (y, v) >> >> ? >> >> I'm using it heavily in my current project, but I don't want to repeat >> somebody else's work, and it seems general enough to be defined somewhere; >> but my quick search on Hackage didn't reveal anything. >> >> I know about arrows; this, however, is something more general, and it's >> instances aren't always arrows. > > Are you aware of generalized arrows [1]? It's still a lot more than > your Something, though.
I've heard of them, but some instances of my Something class aren't categories either, which rules out GArrows too. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
