Neil, I have added missing show functions for CoreFloat and CoreDouble. While testing, I came across this issue: Haskell: module Vt1 where ... y :: Float -> Float y f = case f of 1.0 -> 2.0 3.45 -> 0.2e-4 0.99 -> 7.463 other -> -3.65 Core: Vt1.y v423 = case (YHC.Internal._eqFloat v423 1.0) of Prelude.True -> 2.0 Prelude.False -> -3.65 It looks like a case expression was converted as an if expression. Hopefully this is only a Core problem because: bash$ cat fltest.hs module Main where y :: Float -> Float y f = case f of 1.0 -> 2.0 3.45 -> 0.2e-4 0.99 -> 7.463 other -> -3.65 main = do putStrLn $ show (y 1.0) putStrLn $ show (y 3.45) putStrLn $ show (y 0.99) putStrLn $ show (y 4.56) bash$ yhc fltest.hs Compiling Main ( fltest.hs ) bash$ yhi Main.hbc 2.0 2.0e-5 7.463 -3.65 i. e. the program works OK. -- Dimitry Golubovsky Anywhere on the Web