Re: [Haskell-cafe] [ANN] ghc-typelits-knownnat-0.2: Solving GHCs KnownNat constraints

17 Aug 2016


      Yes, clash is the motivating use case. I wanted to simplify the API of the prelude for the upcoming 1.0 release. Especially to reduce monstrosities such as this: http://hackage.haskell.org/package/clash-prelude-0.10.11/docs/CLaSH-Sized-Fi...

Cheers,

Christiaan
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On 17 Aug 2016, at 19:50, Will Yager  wrote:
Ah. I believe I have run into such issues with Clash, requiring me to add extraneous constraints over the results of addition. I assume this is the motivating use case here?
Great work on this and Typelits-natnormalise!
Will
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On Aug 17, 2016, at 06:11, Christiaan Baaij  wrote:
If you have ever worked with `GHC.TypeLits`, then you have probably encountered an error very similar to:
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• Could not deduce (KnownNat (n + 2))
      arising from a use of ‘natVal’
    from the context: KnownNat n