[GHC] #9586: Implement Traversable/Foldable-Burning-Bridges Proposal

[GHC]

#9586: Implement Traversable/Foldable-Burning-Bridges Proposal
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              Reporter:  hvr         |            Owner:  hvr
                  Type:  task        |           Status:  new
              Priority:  normal      |        Milestone:  7.10.1
             Component:              |          Version:
  libraries/base                     |         Keywords:
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Difficult (2-5
  Unknown/Multiple                   |  days)
       Type of failure:              |       Blocked By:
  None/Unknown                       |  Related Tickets:  #9621
             Test Case:              |
              Blocking:              |
Differential Revisions:  Phab:D209   |
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Comment (by rwbarton):

 Replying to [comment:24 Herbert Valerio Riedel <hvr@…>]:
 > In [changeset:"a07ce1654ac5b8033f2daf9270c6e182415b69ca/ghc"]:
 > {{{
 > #!CommitTicketReference repository="ghc"
 revision="a07ce1654ac5b8033f2daf9270c6e182415b69ca"
 > Generalise `Control.Monad.{when,unless,guard}`
 >
 > Generalise `when`/`unless`from `Monad` to `Applicative` and `guard` from
 > `MonadPlus` to `Alternative` respectively.
 >
 > This was made possible by the AMP and is somewhat related to #9586
 > (but generalising in the context of the AMP instead of the FTP)
 >
 > Reviewed By: ekmett, austin
 >
 > Differential Revision: https://phabricator.haskell.org/D253
 > }}}

 Off-topic for this ticket but why not also generalize `filterM`,
 `forever`, ..., `replicateM_`? Are there hangups about the letter M in the
 names of some of these functions?

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9586#comment:27>
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