You should be giving a type signature to rewrap! That should fix it. Simon | -----Original Message----- | From: glasgow-haskell-users-bounces@haskell.org [mailto:glasgow-haskell-users-bounces@haskell.org] On Behalf Of | Neil Mitchell | Sent: 17 December 2007 16:23 | To: glasgow-haskell-users@haskell.org | Subject: GADT pattern match in non-rigid context | | Hi, | | Upgrading from GHC 6.6 to 6.8 has caused some code to stop working: | | ---------------------------------------------------------------------- | {-# OPTIONS_GHC -fglasgow-exts #-} | | module Data2 where | | data CCompany | | data Paradise :: * -> * where | CC :: Paradise CCompany | | rewrapCC CC = [] | ---------------------------------------------------------------------- | | [1 of 1] Compiling Data2 ( Data2.hs, interpreted ) | | Data2.hs:12:9: | GADT pattern match in non-rigid context for `CC' | Tell GHC HQ if you'd like this to unify the context | In the pattern: CC | In the definition of `rewrapCC': rewrapCC CC = [] | | This code is from the Uniplate benchmarking code, which runs the | Paradise benchmark from SYB on Uniplate, Compos and SYB. The Compos | code uses GADT's, so the program first needs to convert from standard | data structures to GADT's before it can work, then back at the end. | It's the problem of converting from a GADT to a normal data structure | that is failing. | | So is there an easy workaround? Or should I be asking GHC HQ to unify things? | | Thanks | | Neil | _______________________________________________ | Glasgow-haskell-users mailing list | Glasgow-haskell-users@haskell.org | http://www.haskell.org/mailman/listinfo/glasgow-haskell-users