Short version: Is it possible/reasonable to define a single function that accepts a single string or a list of strings (in which case it maps the single-string "flavor" over the list)? Longer version: Thus far I know that Haskell allows me to define a function on a single string, then define another function that maps the first one across a list of strings, as in: *Main> let quote1 s = "\"" ++ s ++ "\"" *Main> "Quux said " ++ quote1 "foo" ++ " loudly" "Quux said \"foo\" loudly" *Main> let quote = map quote1 *Main> quote ["foo", "baz", "bletch"] ["\"foo\"","\"baz\"","\"bletch\""] (BTW, is it standard terminology to say that quote lifts quote1 to lists?) In the above I have different names for the two functions. OO languages such as Java allow me to overload quote to accept either String or List<String> (and return the same type). AFAICT, Haskell's parametric polymorphism allows me to define functions (e.g. length) which deal with "listness" concepts indifferent to the type contained by the list. Am I missing something, or should I admit to OO wrongheadedness and accept that my inability to write a single declaration unifying: quote :: String -> String quote :: [String] -> [String] is an emphatic clue that I should change my expectations? Thanks in advance for any enlightenment shed my way! -jn- -- Beauty of style and harmony and grace and good rhythm depend on simplicity. - Plato