Re: [Haskell-cafe] Haskell type system and the lambda cube

On Sun, May 24, 2009 at 12:18:40PM +0400, Eugene Kirpichov wrote:

Haskell has terms depending on types (polymorphic terms) and types depending on types (type families?), but no dependent types.

But how about undecidability? I'd say that lambda2 or lambda-omega have undecidable type checking, whereas Haskell's Hindley-Milner type system is decidable. From this I get that Haskell's type system can't be one of the vertices of the cube. (BWT, will some future version of Haskell consider including some kind of dependent types?) Petr

2009/5/24 Petr Pudlak :

...

Hi, I'm trying to get some better understanding of the theoretical foundations behind Haskell. I wonder, where exactly does Haskell type system fit within the lambda cube? http://en.wikipedia.org/wiki/Lambda_cube I guess it could also vary depending on what extensions are turned on.

   Thanks, Petr _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

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