Type aliases for TypeError constrains fire during compilation time
Hello!
The following code should compile fine:
module Main where
import GHC.TypeLits (ErrorMessage(Text, ShowType, (:<>:)), TypeError)
type MyError a b = TypeError (ShowType a :<>: ShowType b)
main :: IO ()
main = return ()
but it raises an error during compilation:
Main.hs:5:1: error:
• ab
• In the type synonym declaration for ‘MyError’
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 |