Re: [Haskell-cafe] Mutually recursive modules and google protocol-buffers

On Wed, Jul 16, 2008 at 12:54 AM, Henning Thielemann wrote:

Sooner or later you want generalize your datatypes. Then you can define data A b = A b and you do not need to import B any longer. I do not know if this is a generally applicable approach, but it helped me in some cases.

This only really works if it's "natural" for A to be polymorphic in b. Otherwise you end up with all sorts of irrelevant administrative type parameters polluting your signatures. (I recently had a similar problem with mutually recursive modules; I ended up deciding to write my program in not-Haskell instead, which made me a little sad.) Stuart