Ticket #7066 (new bug)
isInstance does not work for compound types
|Reported by:||edsko||Owned by:||simonpj|
|Type of failure:||None/Unknown||Difficulty:||Unknown|
|Test Case:||Blocked By:|
import Language.Haskell.TH.Syntax data A = A test :: Q [Dec] test = do tp <- [t| (Int, A) |] inst1 <- isInstance ''Show [ tp ] runIO $ print inst1 return 
This prints True even though there is no Show instance for A (the Show instance it finds is for pairs, but it does not verify that there are Show instances for the pair components).