Hi, I was trying to install ad (Automatic Differentiation) but got the following error. I guess the answer is to upgrade my ghc (perhaps someone could confirm) but I am using the Haskell Platform and would rather stick with that. I see from http://hackage.haskell.org/platform/ that the next release is due out in May. Will that be early May? in which case I may well wait a week or will it be late May? in which case I might bite the bullet and upgrade my ghc. Thanks, Dominic Building template-haskell-2.7.0.0... [1 of 7] Compiling Language.Haskell.TH.Syntax.Internals ( Language/Haskell/TH/Syntax/Internals.hs, dist/build/Language/Haskell/TH/Syntax/Internals.o ) [2 of 7] Compiling Language.Haskell.TH.Syntax ( Language/Haskell/TH/Syntax.hs, dist/build/Language/Haskell/TH/Syntax.o ) [3 of 7] Compiling Language.Haskell.TH.PprLib ( Language/Haskell/TH/PprLib.hs, dist/build/Language/Haskell/TH/PprLib.o ) Language/Haskell/TH/PprLib.hs:55:10: Illegal instance declaration for `Show Doc' (All instance types must be of the form (T t1 ... tn) where T is not a synonym. Use -XTypeSynonymInstances if you want to disable this.) In the instance declaration for `Show Doc' Updating documentation index /Users/Test/Library/Haskell/doc/index.html cabal: Error: some packages failed to install: ad-1.3.0.1 depends on template-haskell-2.7.0.0 which failed to install. template-haskell-2.7.0.0 failed during the building phase. The exception was: ExitFailure 1 The Glorious Glasgow Haskell Compilation System, version 7.0.3