[HOpenGL] problem with displayCallback and Double buffering

[Marc A. Ziegert]

does anyone else have this problem?
i want to use double buffering, but swapBuffers does not seem to work.
to set the active window to... the active window (i think that has to work!) does not work, too.
but i am able to compile and run glut examples with double buffering written in c.

coeus at titan ~/Documents/haskell/hopengl/problem $ ghc -package GLUT -package OpenGL first.hs -lglut
coeus at titan ~/Documents/haskell/hopengl/problem $ ./a.out
displayModePossible? ...True
begin swapBuffers
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{-# OPTIONS -fglasgow-exts -fffi #-}

import Graphics.UI.GLUT
import Graphics.Rendering.OpenGL hiding (Double)

dc = do set [clearColor $= Color4 0 0 1 0]
        clear [ColorBuffer,DepthBuffer]
        --flush
        --finish
        putStrLn "begin swapBuffers"
        swapBuffers
        putStrLn "end swapBuffers"
        return ()


main = do getArgsAndInitialize
          set [initialDisplayMode $= [Double,Depth]]
          b <- get displayModePossible
          putStrLn $ "displayModePossible? ..." ++ show b
          w <- createWindow "main"
          set [displayCallback $= dc]
          mainLoop