Nested TH not allowed in declarations
I tried to do the following with the singletons
and derive
libraries:
$(singletons [d|
data CrudRoute = AddR | EditR | DeleteR | ViewR
deriving (Eq,Ord,Enum,Bounded,Show)
data MyRoute = UsersR | ProfileR | RenameR | DogR CrudRoute
deriving (Eq,Ord,Show)
$( derive makeEnum ''MyRoute )
|])
GHC fails with the following error message:
Splices within declaration brackets not (yet) handled by Template Haskell
Here is the github issue where this originated: https://github.com/goldfirere/singletons/issues/135#issuecomment-158936027
Trac metadata
Trac field | Value |
---|---|
Version | 7.10.2 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |