[GHC] #8370: Ranked Instances

[GHC]

#8370: Ranked Instances
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        Reporter:  wvv               |            Owner:
            Type:  feature request   |           Status:  closed
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.6.3
      Resolution:  invalid           |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by carter):

 wvv,
 seems you're actually pointing a problem folks agree on  (would be nice to
 be able to define a child type class and have it instantiate its parents),
 but I think your proposed approach is a bit confusing and overly complex.

 likewise, its very very important to clearly explain the problem statement
 / goal, before jumping into made up notation that no one but you can
 decipher easily.

 likewise, "its easy to implement " is hard to validate, or you'd already
 have a patched ghc with the ideas locally to test it out for usability!
 since you dont, by default you should assume its actually more subtle
 than you claim!  if you want a feature for GHC, and you want a specific
 design that no one else is excited about, you need to cook up the patch
 yourself, and then demonstrate with working code that can actually run,
 that your ideas are good.

 the burden of proof here lies with you.  If you can cookup a patch that
 validates your claims, great. failing that, please read the book i
 suggested, an all the relevant papers in
 http://ghc.haskell.org/trac/ghc/wiki/ReadingList CAREFULLY.

 I repeat, please don't post any new proposals until you have worked
 through the book i have suggested
 http://www.cs.cmu.edu/~rwh/plbook/book.pdf and the relevant parts of the
 reading list.

 Please do that and I look forward to your subsequent involvement in ghc.

 If you have any questions or troubles with those readings, then direct
 your questions to the haskell-cafe mailing list and/or the #haskell IRC
 channel on freenode.

 Please refrain from posting any new proposals/ideas to GHC trac until
 after you have worked through the above reading list, which I anticipate
 will be late February 2014 at the earliest.

 this ticket is closed.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8370#comment:3>
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