[Haskell-cafe] instance Applicative f => Applicative (StateT s f)

[Martijn van Steenbergen]

Hello all,

How do I implement the following?

   instance Applicative f => Applicative (StateT s f)

The implementation of pure is trivial, but I can't figure out an 
implementation for <*>. Is it possible at all, or do I need to require f 
to be a monad?

Thanks in advance,

Martijn.