[GHC] #12976: GHCi displays the kinds of unboxed tuples incorrectly

[GHC]

#12976: GHCi displays the kinds of unboxed tuples incorrectly
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        Reporter:  RyanGlScott       |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  GHCi              |              Version:  8.0.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by goldfire):

 The `(#,#)` type constructor takes 4 arguments, `(r1 :: RuntimeRep)`, `(r2
 :: RuntimeRep)`, `(a :: TYPE r1)`, and `(b :: TYPE r2)`. Because there is
 no type-level lambda, it ''must'' take these arguments in order. So we
 cannot supply the third argument (the `Int#` in the `(#,#) Int#` case)
 without supplying the second. Initially, this second argument is a
 unification variable, but this gets defaulted to `PtrRepLifted` before
 printing.

 Does that explain it?

 And I have no idea what's going on with TH. That looks like a separate
 ticket to me.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12976#comment:4>
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