[GHC] #10776: DataKinds promotion of String -> Symbol and Natural -> Nat

[GHC]

#10776: DataKinds promotion of String -> Symbol and Natural -> Nat
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        Reporter:  htebalaka         |                Owner:
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  7.10.2
  checker)                           |
      Resolution:                    |             Keywords:  DataKinds
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 dmcclean):

 A hearty amen on this one, especially unifying `Natural` with `Nat`.

 Regarding the `String` objection perhaps it would be better to merely
 flesh out `Symbol` at the term level? With an `IsString` instance and so
 forth? Because as mentioned unifying it with `String` is problematic since
 `String` is a type synonym for a list of characters.

 I also agree with Richard's comments regarding the desirability of type-
 level literals of all stripes (or at least other stripes). I'm not sure if
 floating-point numbers or characters specifically are useful, but integers
 and rationals most definitely are of use to the `dimensional` library. We
 have home-brewed ones, but it is a lot of machinery, isn't interoperable
 with the few other flavors of home-brewed ones on the market, and isn't
 the lifted version of `Rational` or `Integer` so you can't use the lifted
 kinds that go with the types of term-level structures that include
 rational or integers.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10776#comment:3>
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