[Haskell-beginners] Parsing Revisited

I believe it might be beneficial for me to ask a more general question than I asked in 'Parsing Custom TeX': Given a set of combinators that parse specific parts of a document, how can you string them together so that you can get the whole document parsed? Within this, a consideration for extraneous whitespace should be considered - where you might have specific rules for when to drop whitespace. Thank you again. Jeff.