Hello all,
Chessai and I are excited to announce a release candidate for `mtl`: [`mtl-2.3-rc3`](https://github.com/haskell/mtl/releases/tag/v2.3-rc3)!
## Timeline
The timeline for release will be as follows:
- This announcement marks the start of the timeline
- We will give 2 weeks of testing before considering release
- If no major issues are filed before then, `mtl-2.3-rc3` will be released as `mtl-2.3`, and if issues are found, they will be amended, and a new release candidate will be announced, resetting the 2 week period.
To test `mtl-2.3-rc3` for yourself, please feel free to add the following to your `cabal.project`:
```
source-repository-package
type: git
location: https://github.com/haskell/mtl.git
tag: 5d0f62b8007bb96e49f36a5544741cfe96a97130
```
or, if you're a stack user add this entry to your `extra-deps`:
```
commit: 5d0f62b8007bb96e49f36a5544741cfe96a97130
```
And make sure to adjust all bounds/`allow-newer` accordingly. Please note that this release of `mtl` is a full major version release, and *will be the last of the 2.x series before work begins on updating the mtl class hierarchy*.
## Changelog
* Add instances for `Control.Monad.Trans.Writer.CPS` and `Control.Monad.Trans.RWS.CPS` from `transformers` 0.5.6 and add `Control.Monad.Writer.CPS` and `Control.Monad.RWS.CPS`.
* `Control.Monad.Cont` now re-exports `evalCont` and `evalContT`
* Add `tryError`, `withError`, `handleError`, and `mapError` to
`Control.Monad.Error.Class`, and re-export from `Control.Monad.Except`.
* Remove `Control.Monad.List` and `Control.Monad.Error`
* Remove instances of deprecated `ListT` and `ErrorT`
* Remove re-exports of `Error`
* Add instances for `Control.Monad.Trans.Accum` and `Control.Monad.Trans.Select`
* Remove re-exports of `Control.Monad`, `Control.Monad.Fix` and `Data.Monoid` modules
I'd like to thank the many contributors who offered patches, tickets, and other help in the preparation of this release. We appreciate all of your help!
Happy hacking!
Emily
