I'd like to have a state monad with the feature that I can somehow annotate using the type system that some functions are only going to read the state and not modify it. Such read-only functions are only permitted to call other read-only functions, whereas state-modifying functions can call both read-only and other state-modifying functions.
How can I do this? It does not seem to be straightforwardly doable with Control.Monad.State. --ken _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
