[Haskell-cafe] untyped printf

[Henning Thielemann]

On Fri, 4 Dec 2020, Ben Franksen wrote:

> Wow, that simple. Thanks Henning, my untangled brain feels a lot better :-)

I tangled my brain because I expected that it must be possible in Haskell 
98 ...

... and actually it is:


import Text.Printf (PrintfType, printf)

type Value = Int

printfv :: (PrintfType printf) => String -> [Value] -> printf
printfv fmt [] = printf fmt
printfv fmt (x:xs) = printfv fmt xs x

format :: String -> [Value] -> String
format fmt = printfv fmt . reverse