Monad of no `return` Proposal (MRP): Moving `return` out of `Monad`

wren romano wren at
Mon Sep 28 21:42:10 UTC 2015

On Sat, Sep 26, 2015 at 6:04 PM, Richard Eisenberg <eir at> wrote:
> Thanks for making this proposal.
> I'm leery of the breakage that this would cause. But, there has been no chorus of voices complaining about breaking changes in the recent past (AMP and changes to Typeable are top on my mind), so perhaps our community is more tolerant of breakage than I would guess.

Though I'd love to see pure/return unified, I almost wonder if it'd be
a good idea to wait a bit on this. By which I mean, rather than having
a bunch of little breaking changes as we try to fix things piecemeal,
perhaps it'd be better to fold this proposal (and similar ones) into
the next Haskell' report (assuming we can actually ship it this time).
That way we can just have a big break-the-world change in the
transition to Haskell2020 (or whatever).

Not sure if that's the best approach, especially given the difficulty
in getting Haskell2020 finalized, but it might be worth thinking

Live well,

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