[GHC] #13795: :kind! is not expanding type synonyms anymore

[GHC]

#13795: :kind! is not expanding type synonyms anymore
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        Reporter:  Hjulle            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  GHCi              |              Version:  8.0.2
      Resolution:                    |             Keywords:  newcomer
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by goldfire):

 IIRC, this was a deliberate choice: the idea was that type families are
 best understood after expansion but type synonyms are best understood
 without expanding. The process used in `:kind!` even looks through type
 synonyms to see if there are more type family reductions possible.

 This is all a matter of taste. We ''could'' change it (easily). Would it
 surprise other users? Perhaps.

 This is something wider community input might help to enlighten, but a
 full ghc-proposal seems rather heavy. I don't know of a lighter-weight way
 forward, though.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13795#comment:4>
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