On Tue, 3 Aug 2010 16:24:54 +0200, Stefan Holdermans <[email protected]> wrote: > Nicolas, > > > OK, I better understand now where we disagree. You want to see in the type > > whether or not the free theorem apply, I want them to always apply when > > no call to unsafe function is made. > > Implementing your suggestion would make me feel uncomfortable. Turning seq > into an unsafe operations effectively places it outside the language, like > unsafePerformIO isn't really part of the language (in my view, at least). But > experience has made it clear that there are plenty of occasions in which we > cannot really do without seq (even though its presence in the language is > prominent subject of debate).
If we ignore the solution using Typeable for now. The actual seq would be considered unsafe but seq would be re-introduced as a method of a type class with instances for many types but not for functions. So in this view only forcing functions would be considered "out of the language". -- Nicolas Pouillard http://nicolaspouillard.fr _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
