[Haskell-cafe] Is there Functor instance of Enumerator'

[yi huang]

Say i want to compose  Enumerator ByteString m b and Iteratee Builder
m b, so I try to transform the enum to Enumerator Builder m b,
providing function ByteString -> Builder. It's like implement a
Functor instance for Enumerator. But i failed, there are no way to
make type system happy.
Am I right that there is no Functor instance of Enumerator?

-- 
http://www.yi-programmer.com/blog/