Hi Haskell gurus,
I'm learning Haskell now and here I'm quite puzzled over some code
about Monad Transformers. The code is like:
type NDS a = StateT ProblemState [] a
getVar :: Var -> NDS (Maybe Value)
getVar v = do vs <- gets vars
return $ lookup v vs
What puzzles m
On Tue, Nov 22, 2005 at 05:26:00PM -0700, Fan Wu wrote:
>type NDS a = StateT ProblemState [] a
>
>getVar :: Var -> NDS (Maybe Value)
>getVar v = do vs <- gets vars
> return $ lookup v vs
>
>
> What puzzles me is that, I think the Monad of the do block shall be
> the
