How bad would it be for containers to depend on transformers?

Edward Kmett ekmett at
Wed Jun 22 18:24:36 UTC 2016

If we're just talking about building one or two transformers then I'd say we should avoid incurring the dependency. The outcry would far far outweigh the code sharing advantage for one or two types. E.g. base duplicates State internally for mapAccumL for instance for this sort of reason.

Sent from my iPad

> On Jun 22, 2016, at 12:58 PM, David Feuer <david.feuer at> wrote:
> Currently, containers does not depend on transformers, so it has to duplicate its functionality or just do without. Since transformers is also a GHC boot package, I believe it should be feasible to make containers depend on it. To what extent would that reduce 
> parallelizability of GHC builds or otherwise make people mad?
> David
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