2010/7/14 Felipe Lessa <felipe.le...@gmail.com>: > On Wed, Jul 14, 2010 at 8:25 AM, Arnaud Bailly <arnaud.oq...@gmail.com> wrote: >> Hello, >> I would like to construct a collection of function-like objects on >> which I could apply some value, in a typesafe and clean way. > > You could use Data.Typeable.cast [1] > > [1] > http://haskell.org/ghc/docs/6.12.1/html/libraries/base-4.2.0.0/Data-Typeable.html#v%3Acast > [snip]
Or maybe Data.Dynamic with type Callables = Map String Dynamic You can extract the function with fromDynamic in a type-safe way (it returns a Maybe). Probalby you might want 'invoke' to return a Maybe too (just like Felipe did). Cheers, Thu _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe