Re: [Haskell-cafe] Polymorphic variants
On Thursday 26 July 2007 00:07:23 Josef Svenningsson wrote: On 7/26/07, Jon Harrop [EMAIL PROTECTED] wrote: Does Haskell have anything similar to OCaml's polymorphic variants? No as such, but it's possible to simulate them. As always Oleg was the one to demonstrate how: http://okmij.org/ftp/Haskell/generics.html Thank you. Is there any interest in adding polymorphic variants to Haskell? I think it is fair to say that OCaml has shown them to be an extremely useful construct (more common than objects in OCaml, for example). -- Dr Jon D Harrop, Flying Frog Consultancy Ltd. OCaml for Scientists http://www.ffconsultancy.com/products/ocaml_for_scientists/?e ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Polymorphic variants
On 7/26/07, Jon Harrop [EMAIL PROTECTED] wrote: Does Haskell have anything similar to OCaml's polymorphic variants? No as such, but it's possible to simulate them. As always Oleg was the one to demonstrate how: http://okmij.org/ftp/Haskell/generics.html Cheers, Josef ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Polymorphic variants
Does Haskell have anything similar to OCaml's polymorphic variants? They act as inferred sum types: # let rec eval = function | `Int n - n | `Add(f, g) - eval f + eval g | `Mul(f, g) - eval f * eval g;; val eval : ([ `Add of 'a * 'a | `Int of int | `Mul of 'a * 'a ] as 'a) - int = fun -- Dr Jon D Harrop, Flying Frog Consultancy Ltd. OCaml for Scientists http://www.ffconsultancy.com/products/ocaml_for_scientists/?e ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
