A small stylistic question: what's the "best" way to build strings containing other values? For example, I have: data Process = Stop | Prefix String Process | External Process Process instance Show Process where show Stop = "Stop" show (Prefix l p) = "(" ++ l ++ "->" ++ show p ++ ")" show (External p q) = "(" ++ show p ++ " [] " ++ show q ++ ")" but to me the extensive use of ++ is not particularly readable. I'm very fond of Python's interpolation approach, where we'd have something like the following for the External case: def __str__(self): return "(%s [] %s)" % (self.p, self.q) which to me seems clearer, or at least easier to work out roughly what the string's going to look like. (The %s does an implicit "convert to string", btw). Is there a facility like this in Haskell? Or something else I should be using, other than lots of ++ ? Thanks, -Andy -- Andy Gimblett Computer Science Department University of Wales Swansea http://www.cs.swan.ac.uk/~csandy/