[GHC] #12822: Cleanup GHC verbosity flags

[GHC]

#12822: Cleanup GHC verbosity flags
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        Reporter:  hsyl20            |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  low               |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
                                     |  newcomer,flags
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 bgamari):

 I wrote this in response to captaintrunky's query on `ghc-devs`,

 > Sergey Bykov <captaintrunky at gmail.com> writes:
 >
 >> Hi, I'm working with the #12822 task, which is a refactoring for the
 >> verbosity flag. It should be reimplemented in a way, similar to the
 >> 'optimization' flag. After studying the codebase, specifically
 >> *optLevelFlags*, I'm stuck with the following questions:
 >>
 >>  1. Should I add a new data 'VerbosityFlag' similar to GeneralFlag,
 >>     DumpFlag, etc or should I extend any of existing data types?
 >>  2. How to determine a set of verbosity options to implement? Is
 >>     grepping through all the codebase and adding corresponding options
 a
 >>     good approach?
 >>
 > As I understand it, the task is to split up the current -v<n> flags into
 > distinct flags. The current role of -v is described roughly in
 > Note [Verbosity levels] (although it references -ddump-most and
 > -ddump-all, which don't exist anymore).
 >
 > Grepping the source tree (e.g. for "verbosity dflags") would indeed be a
 > good way to find the various places it's used. For now let's just add
 > the new flags to GeneralFlag. If there are enough that GeneralFlags
 > becomes bloated we can refactor later.
 >

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12822#comment:7>
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