On Mon, May 02, 2011 at 09:25:06PM +0000, C Rodrigues wrote: > > I'm re-sending this e-mail, hopefully with proper line breaks this time. > > I was experimenting with using GADTs for subtyping when I found something > interesting. Hopefully someone can satisfy my curiosity. > > Here are two equivalent GADTs. My understanding was that GHC would translate > "Foo" and "Bar" into isomorphic data types. > However, GHC 6.12.3 generates better code for 'fooName' than for 'barName'. > In 'fooName', there is no pattern match against 'FooExtra'. > In 'barName', there is a pattern match against 'BarExtra'. What > makes these data types different?
Not a real answer to your question, but have you tried this with GHC 7.0.3? The type checker changed a lot between 6.12 and 7 and it may now behave more consistently (although I do not know for sure). -Brent _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
