> I’m a newcomer to Haskell and mailing list, so I am not sure if my question is proper.
> I use notepad++ to learn Haskell now. Are there any suggestions or conventions which can help me learn Haskell?
> Best regards,
I think for learning "code", as in writing nice code, get yourself the Hlinter  running.
It really spots great improvements and some very haskelly ways.
For Learning purposes I would suggest that you first "try it your way" step by step, and check every step with hlint.
So: fun1 -> Hlint -> fun2 -> Hlint
Additionally you might want to enable a spell-checker (like, a normal one, for english).
Last thing you might find very useful is a local Hoogle  install.
It's amazingly convenient if you want to know, e.g. the function which gives a length of a list, but you don't remember if it was len, length, size, count ...
So you just search for [a] -> Int and voila.
Second Hoogle can help you find similar functions to what you are currently building, often you are implementing something that is somewhere as a higher order function already.