Types are not normalized in instance declarations
Consider the example below. It does not compile, but replacing 5*2 by 10 makes it compile. This is quite annoying since it forces me to do the normalization that the computer is really much better at doing.
module NatInstance where
import GHC.TypeLits
type N = 5 * 2
data D (n :: Nat) = D
instance Show (D N) where show _ = ""
Trac metadata
Trac field | Value |
---|---|
Version | 8.0.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |