There was (two days ago or so) a sequence of posts about this. You need the command line option -ffi. -- Hal Daume III "Computer science is no more about computers | hdaume@isi.edu than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume On Tue, 22 Oct 2002, Francis Girard wrote:

Hello,

I'm a beginner trying to use FFI. I copied the example given in :

The Glasgow Haskell Compiler User's Guide, Version 5.04 Chapter 8. Foreign function interface (FFI)

-------------------------------------------------------------------------- module Foo where

foreign export ccall foo :: Int -> IO Int

foo :: Int -> IO Int foo n = return (length (f n))

f :: Int -> [Int] f 0 = [] f n = n:(f (n-1)) --------------------------------------------------------------------------

Copied it verbatim. And simply tried to compile it using "ghc -c Foo.hs -o Foo.o" and always got the error :

Type signature given for an expression (at the line following the "foreign export")

I then tried to import the "Foreign" and "Foreign.C" modules but it didn't change anything.

I am missing something and I would be VERY grateful to anyone that tells me what.

Thank you

Francis Girard Le Conquet (France) Francis.Girard@free.fr _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users