Skip to content
Snippets Groups Projects

Error in optCoercion

    • Closed Issue created by Simon Peyton Jones @simonpj

    This program fails Lint after a run of the simplifier.

    {-# LANGUAGE TypeOperators, UndecidableSuperClasses, KindSignatures, TypeFamilies, FlexibleContexts #-}

module T11728a where

import Data.Kind
import Data.Void

newtype K a x = K a
newtype I   x = I x

data (f + g) x = L (f x) | R (g x)
data (f × g) x = f x :×: g x

class Differentiable (D f) => Differentiable f where
  type D (f :: Type -> Type) :: Type -> Type

instance Differentiable (K a) where
  type D (K a) = K Void

instance Differentiable I where
  type D I = K ()

instance (Differentiable f₁, Differentiable f₂) => Differentiable (f₁ + f₂) where
  type D (f₁ + f₂) = D f₁ + D f₂

instance (Differentiable f₁, Differentiable f₂) => Differentiable (f₁ × f₂) where
  type D (f₁ × f₂) = (D f₁ × f₂) + (f₁ × D f₂)

    Originally reported in #11728 (closed), but it's a totally different problem.

    Richard has nailed it already... patch coming from him.

    Edited
    To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information

    Child items ...

    • Activity

    Please register or sign in to reply