[Haskell-beginners] Type definition doesn't match with number of arguments

[Emanuel Koczwara]

Hi,

  Please help me understund this code:

http://hackage.haskell.org/packages/archive/daemons/0.1.2/doc/html/src/Control-Pipe-C3.html#commandSender

  The type of commandSender is:

(Serialize a, Serialize b) => a -> Handler (Maybe b)

  But definition looks like this:

commandSender command reader writer = do ...

  As I understund, command has type a and this function returns Handler
(Maybe b). reader and writer doesn't fit here. What's going on?

Emanuel