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Haskell pattern error when using get

A little confused by the results that I get. Using the following:

GHCi, version 7.4.2: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Prelude> :m + Language.Haskell.TH

I get this successful result:

 Prelude Language.Haskell.TH> runQ [d| data X = X |] [DataD [] X_0 [] [NormalC X_1 []] []]

But I get this error:

 Prelude Language.Haskell.TH> runQ [d| data X = X deriving Show |] <interactive>:4:30: The exact Name `X' is not in scope Probable cause: you used a unique name (NameU) in Template Haskell but did not bind it In the Template Haskell quotation [d| data X = X deriving (Show) |] In the first argument of `runQ', namely `[d| data X = X deriving (Show) |]' In the expression: runQ [d| data X = X deriving (Show) |]

Can't I get Show when using Template Haskell?

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1 answer

It looks like it was a bug in the GHC that was fixed in version 7.6.1:

 $ ~/bin/ghc-7.6.1/bin/ghci GHCi, version 7.6.1: http://www.haskell.org/ghc/ :? for help [...] Prelude> :set -XTemplateHaskell Prelude> import Language.Haskell.TH Prelude Language.Haskell.TH> runQ [d| data X = X deriving (Show) |] [...] [DataD [] X_0 [] [NormalC X_1 []] [GHC.Show.Show]]
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