On Wed, Jan 7, 2009 at 12:58 PM, Jeff Heard
And how do I encode
a{ mousePositionf = b }
in template haskell without using the [| |] syntax, so that I can use mkName?
Whenever I have a question like that, I just ask ghci: $ ghci -fth ghci> :m Control.Monad.Identity Language.Haskell.TH ghci> runQ [| 1 + 1 |] InfixE (Just (LitE (IntegerL 1))) (VarE GHC.Num.+) (Just (LitE (IntegerL 1))) ghci> runQ [| \x -> x { runIdentity = 1 } |] LamE [VarP x_1] (RecUpdE (VarE x_1) [(Control.Monad.Identity.runIdentity,LitE (I ntegerL 1))]) Note that GHCi shows TH names without "mkName" or quotes, so you need to add those. But it shows you the structure you want to generate. You can also use $() and [| |] inside [| |] to generate additional data in TH directly: ghci> runQ $ do { VarE n <- [| runIdentity |] ; [| \x -> $(recUpdE [| x |] [ fmap (\e -> (n,e)) [| 1 |] ]) |] } LamE [VarP x_2] (RecUpdE (VarE x_2) [(Control.Monad.Identity.runIdentity,LitE (I ntegerL 1))]) Note the "VarE n <- [| identifier |]" trick to extract the name from an identifier. -- ryan