Re: [Template-haskell] Language.Haskell.THSyntax data types deriving Eq

On Saturday 09 August 2003 3:58 pm, Andre Pang wrote:

Is there a reason why any/all of the data types in Language.Haskell.THSyntax (such as Dec, Stmt, and Type) don't derive Eq? I'm thinking that it would be useful for test suites, in particular.

I recently found myself wanting that. The tricky one is Eq for types that contain forall. The derived instances would be wrong if we want to allow alpha conversion. Hand-writing a correct instance is pretty tedious. -- Alastair