[Haskell-cafe] Automatic derivation (TemplateHaskell?)
joelr1 at gmail.com
Thu Apr 5 06:04:41 EDT 2007
This is in Language.Haskell.TH.Syntax which is imported at the top of
Data/Derive/TH.hs so I don't understand the cause of the error
instance Functor Q where
fmap f (Q x) = Q (fmap f x)
Copying the above into TH.hs gives me
Preprocessing library derive-0.1...
Preprocessing executables for derive-0.1...
[4 of 9] Compiling Data.Derive.TH ( Data/Derive/TH.hs, dist/build/
Data/Derive/TH.hs:23:10: Not in scope: data constructor `Q'
Data/Derive/TH.hs:23:17: Not in scope: data constructor `Q'
But Q is exported by Languave.Haskell.TH.Syntax !!!
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