23 Oct
2006
23 Oct
'06
6:23 p.m.
Conor McBride wrote:
magic :: Zero -> a magic _ = error "There's magic, as no such thing!"
It's a little frustrating to have to define this function lazily. I prefer the strict definition with no lines, but it isn't valid Haskell!
This issue comes up a lot with GADTs. For instance: data MyGADT a where MyInt :: MyGADT Int MyChar :: MyGADT Char never :: MyGADT Bool -> a Annoyingly, this doesn't compile without adding a definition line mentioning a bottom value. -- Ashley Yakeley