[GHC] #14391: Make the simplifier independent of the typechecker

[GHC]

#14391: Make the simplifier independent of the typechecker
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        Reporter:  nomeata           |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.3
      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):  Phab:D4503
       Wiki Page:                    |
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Comment (by simonpj):

 Interesting!

 One way to avoid the need for `.hs-boot` files would be to rename-and-
 typecheck each SCC as a whole.  (Implementing this idea would make an
 excellent project, BTW.)

 If we did that, then yes, reducing SCC sizes would become highly relevant.
 (Until we implement it, I'm not sure that reducing SCC sizes is that
 important.)

 I had a look at the top candidate: the import of `TcSplice` in
 `TcRnMonad`.  I think it'd be very simple to untangle.   It's only needed
 to allow the call to `runRemoteModFinalizers`. But I think you could
 easily have
 {{{
   th_modfinalizers_var :: IORef [(TcLclEnv, ThModFinalizers)]
 }}}
 and then `TcRnMonad` would not need to mention `runRemoteModFinalizers`.
 I think that'd be a straight improvement, and we should do it regardless.
 Would you like to try that?  It's a rather simple change.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14391#comment:35>
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