Dear Cafe, is there a library that provides an "abstract representation of file and directory pathnames"? This had been discussed before - e.g., https://mail.haskell.org/pipermail/libraries/2007-December/008769.html (it's one message of a longer thread) That message references an obsolete (?) Java library, they now have https://docs.oracle.com/en/java/javase/13/docs/api/java.base/java/nio/file/F... It seems that https://hackage.haskell.org/package/filepattern-0.1.1/docs/System-FilePatter... does cover typical usage. It is based on FilePath = String, and its implementation has some "++"-ing. That indicates that an abstraction layer is missing - or, that such a layer is indeed not required? - J.W.