パスの中のファイル名を得る

System.FilePathモジュールのtakeFileNameが使えます。

$ ghci
GHCi, version 6.12.2: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
Prelude> :module System.FilePath
Prelude System.FilePath> takeFileName "foo/bar/baz"
Loading package filepath-1.1.0.4 ... linking ... done.
"baz"