On Monday 05 December 2011, 13:44:25, Alexander.Vladislav.Popov wrote:
Why the separate compilation? Can't you compile them in one go?
Sorry for a stupid question, how is it?
Not stupid at all. I'm not an expert in matters FFI, so I don't know if it works in all situations, but for simple cases at least, you can compile in one go listing .hs and .c files on the command line. For a foreign import: // hsFibo.hs: {-# LANGUAGE ForeignFunctionInterface #-} module Main (main) where import System.Environment (getArgs) foreign import ccall unsafe "fibo" c_fibo :: Int -> Int main :: IO () main = do args <- getArgs let n = case args of (a:_) -> read a _ -> 14 print (c_fibo n) // Fibonacci.c int fibo(int n){ int a = (n&1) ? 0 : 1, b = (n&1) ? 1 : 0; while(n > 1){ a += b; b += a; n -= 2; } return b; } $ ghc -O2 hsFibo.hs Fibonacci.c [1 of 1] Compiling Main ( hsFibo.hs, hsFibo.o ) Linking hsFibo ... $ ./hsFibo 21 10946 For a foreign export it's a bit more complicated, as you would have to generate the .h file(s) first by other means (if all your exported functions are compatible with the implicit types for C functions [pre C99, iirc], you can get away without the header, but you'll get warnings about implicit declarations). But with appropriate headers, you can compile in one go, $ ghc -O2 -shared -dynamic -fPIC Export.hs useExport.c -o theexport.so (if you use a C main to create an executable, also pass -no-hs-main).
And one more question, please: how I can export genexPure :: [String] -> [String] to achieve all preferences of lazy list? Not all array at once, but to get someting like an iterator, what I can call to get new genex.
Pass. I have no idea how to do that.