Proposal to solve the `EitherT` problem.
David Luposchainsky
dluposchainsky at googlemail.com
Tue Aug 13 10:36:16 CEST 2013
Morning,
Another discussion that didn't reach conclusion: "Proposal to solve the
`EitherT` problem." Let's do some proposal cleanup :-)
On 2013-06-16 23:52, Gabriel Gonzalez wrote:
> Approach 2: Add `EitherT` to `transformers` alongside `ErrorT` and
have them both implement `MonadError`.
That's the one I would recommend.
- Doesn't break anything, and gets rid of the "exception-vs-error"
discussion.
- Not all uses of Either are to distinguish between success and failure,
sometimes it's just a convenient way of short-circuiting.
- Fits in well with all the other transformers of type "MonadT".
- MonadError instance makes possible use as throw-catch-y transformer clear.
David
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