Why doesn't this Template Haskell program work?

Sean Seefried seefried@itee.uq.edu.au
Mon, 13 Jan 2003 12:50:14 +1000


I compiled the following program with ghc-5.05.20030109

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import Language.Haskell.THSyntax

main = putStrLn (show $(lift ('a', 'b')))

instance (Lift a, Lift b) => Lift (a,b) where
     lift (a,b) = tup [lift a, lift b]

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and received the following error message

-------

ghc --make -fglasgow-exts -package haskell-src -package haskell98 
Main.hs -o test
Chasing modules from: Main.hs
Compiling Main             ( Main.hs, ./Main.o )
Loading package base ... linking ... done.
Loading package haskell98 ... linking ... done.
Loading package haskell-src ... linking ... done.
ghc-5.05.20030109: panic! (the `impossible' happened, GHC version 
5.05.20030109):
         nameModule zdfLiftZ2T{-a1dB-}

Please report it as a compiler bug to glasgow-haskell-bugs@haskell.org,
or http://sourceforge.net/projects/ghc/.

------

Why? Because if I compile the following program,

--------

import Language.Haskell.THSyntax

main = putStrLn (show $(tup [lift 'a', lift 'b']))

--------

it works just fine.

Also, is the template-haskell mailing list active?

Sean Seefried