[GHC] #14488: Can't define a lens for a field with a constraint

[GHC]

#14488: Can't define a lens for a field with a constraint
-------------------------------------+-------------------------------------
        Reporter:  int-index         |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.2
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  GHC rejects       |            Test Case:
  valid program                      |  typecheck/should_compile/T14488
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4213
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"0db4627b8baf3255cf16725f8acdd69e27f0ab85/ghc" 0db4627/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="0db4627b8baf3255cf16725f8acdd69e27f0ab85"
 Test Trac #14488

 Summary:
 The refactoring in 3f5673f34a2f761423027bf46f64f7499708725f also fixed a
 previously unreported issue in the typechecker that prevented defining a
 lens to a record field with a constraint. This patch adds a regression
 test.

 Test Plan: make test TEST=14488

 Reviewers: bgamari

 Reviewed By: bgamari

 Subscribers: int-e, rwbarton, thomie

 GHC Trac Issues: #14488

 Differential Revision: https://phabricator.haskell.org/D4213
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14488#comment:5>
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