GHC doesn't have any way to let you "plug in" new error messages. I imagine you mean in the type inference engine? Can you characterise more precisely what you want, perhaps by example. I do urge you to read the Utrecht work; they have done tremendous stuff on user-defined type rules and associated user-defined error messages. Simon | -----Original Message----- | From: glasgow-haskell-users-bounces@haskell.org [mailto:glasgow-haskell-users- | bounces@haskell.org] On Behalf Of Daniel Gustafsson | Sent: 21 January 2010 18:20 | To: glasgow-haskell-users@haskell.org | Subject: Scriptable error messages | | Hello | | Me and a fellow student are taking a course named Frontiers of | Programming Languages, and in this course we should do a project with | something. A while ago we were at a presentation of Feldspar, a | Embedded Domain Specific Language, and one of the negative points of | using haskell was that the error messages could be cryptic due to the | various ways it was implemented. | | So we are now looking into the possibility of adding your own error | messages to GHC as our project. We have about 8 weeks to implement, | either all or some proof of concept. As such we are looking for | comments, ideas and suggestions. Is this doable in GHC?, or what is | needed. | | Thanks | | Daniel Gustafsson | Simon Edwardsson | Chalmers University of Technology (Gothenburg, Sweden) | _______________________________________________ | Glasgow-haskell-users mailing list | Glasgow-haskell-users@haskell.org | http://www.haskell.org/mailman/listinfo/glasgow-haskell-users