[Haskell-cafe] Concept for "equal but unknown"

[martin]

Am 10/02/2015 um 04:45 PM schrieb Marcin Mrotek:
> Hello,
> 
> Do you mean something like variable unification in Prolog or Oz? Maybe
> something like this could help you:
> https://hackage.haskell.org/package/monad-unify-0.2.2/docs/Control-Monad-Unify.html
> or https://hackage.haskell.org/package/unification-fd Disclaimer: I've
> never used either of those packages.

Well it was no coincidence that I invented the joke term "covariant unification", because I had a hunch that this has
something to do with unification.

Thanks for the links.