[GHC] #13955: Backpack does not handle unlifted types

[GHC]

#13955: Backpack does not handle unlifted types
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        Reporter:  andrewthad        |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  low               |            Milestone:
       Component:  Compiler          |              Version:  8.2.1-rc2
      Resolution:                    |             Keywords:  backpack
                                     |  LevityPolymorphism
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 Ben Gamari <ben@…>):

 In [changeset:"fd8b044e9664181d4815e48e8f83be78bc9fe8d2/ghc"
 fd8b044e/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="fd8b044e9664181d4815e48e8f83be78bc9fe8d2"
 Levity polymorphic Backpack.

 This patch makes it possible to specify non * kinds of
 abstract data types in signatures, so you can have
 levity polymorphism through Backpack, without the runtime
 representation constraint!

 Signed-off-by: Edward Z. Yang <ezyang at cs.stanford.edu>

 Test Plan: validate

 Reviewers: andrewthad, bgamari, austin, goldfire

 Reviewed By: bgamari

 Subscribers: goldfire, rwbarton, thomie

 GHC Trac Issues: #13955

 Differential Revision: https://phabricator.haskell.org/D3825
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13955#comment:6>
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