On Wed, Oct 2, 2013 at 6:57 PM, Stijn van Drongelen <rhym...@gmail.com>wrote:
> > On Wed, Oct 2, 2013 at 5:36 PM, Roman Cheplyaka <r...@ro-che.info> wrote: > >> * Stijn van Drongelen <rhym...@gmail.com> [2013-10-02 15:46:42+0200] >> > I do think something has to be done to have an Eq and Ord with more >> strict >> > laws. >> > >> > * Operators in Eq and Ord diverge iff any of their parameters are >> bottom. >> >> This outlaws the Eq instances of lists, trees, and other (co)recursive >> types. >> >> Furthermore, in this formulation, even Eq for tuples is illegal, because >> >> (undefined, something) == somethingElse >> >> is going to diverge. >> >> Roman >> > > I knew this was going to bite me in the ass. Let me try again: > > * Operators in Eq and Ord may only diverge when any of their parameters > are bottom. > What am I thinking. Scratch that.
_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
