16 Aug
2009
16 Aug
'09
9:50 p.m.
On Sunday 16 August 2009 8:35:19 pm Antoine Latter wrote:
But with those, the number of arguments is still known at compile time, correct?
{-# LANGUAGE Rank2Types #-} import Text.Printf import System.Environment nprintf :: PrintfType t => Int -> Int -> t nprintf n e = aux (printf str) n where str = concat $ replicate n "%d" aux :: PrintfType t' => (forall t. PrintfType t => t) -> Int -> t' aux pf 0 = pf aux pf n = aux (pf e) (n-1) main = do (n:e:_) <- map read `fmap` getArgs nprintf n e :: IO () ------------------------------------------------------------------------ % ./Var 2 5 55 % ./Var 6 5 555555 Voila. -- Dan