[GHC] #16232: Add setField to HasField

[GHC]

#16232: Add setField to HasField
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        Reporter:  adamgundry        |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.10.1
       Component:  Compiler (Type    |              Version:  8.7
  checker)                           |
      Resolution:                    |             Keywords:  ORF
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 simonpj):

 I suggest taking the direct path, and generate an update function for each
 field.  Its more work than Matthew says because we may need to evaluate
 the argument (for strict constructors) or unbox it (if the argument is
 UNPACKed).

 This would ''replace'' the selector function would it not? The new
 function is a selector and update function?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16232#comment:2>
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