Brandon S. Allbery KF8NH wrote:
On Sep 25, 2007, at 5:56 , Andrew Coppin wrote:
More seriously, I have no idea how you'd implement this in Haskell. Presumably the standard show instance for Int, Double, etc. is in native C? You could probably reimplement it in Haskell for the integer case, but not for floating-point...
Actually, Text.Printf is pure Haskell. (Very *scary* Haskell: deep type hackery is needed to make it work. Don't try to understand PrintfType. :)
Forget PrintfType - I can't even understand the haddoc page yet! (printf performs I/O, yet it is outside the I/O monad. It seems to accept an arbitrary number of arguments, which is obviously impossible. It's *almost* as scary as the original. Although the original will crash your program is you use it wr... oh, so does this one. Cool.)