Haskell printf to string

Text.Printf might be what you need.

Yes, it's in the Text.Printf module, and it's just called printf.

> import Text.Printf
> let x = 1.14907259
> putStrLn . printf "%.2f" $ x
1.15

Note that the return type of printf is overloaded, so that it's capable of returning a String (as in the example above) but it's also capable of returning an I/O action that does the printing, so you don't actually need the call to putStrLn:

> printf "%.2f\n" x
1.15