Sun, 6 May 2001 11:29:18 -0600 (MDT), Alastair Reid <[EMAIL PROTECTED]> pisze:
>> foreign export dynamic is a shortcut for importing an automatically
>> generated nontrivial C function, with argument type not conforming to
>> regular imports, which could not be written by hand.
>
> I don't get it. How do you use a function with a type like:
>
> (Int -> IO Int) -> Addr
>
> to import a C function?
*This* is an imported function.
Well, if I wanted to make it by hand, I would have to make a StablePtr
before, because I can't pass (Int -> IO Int) to a foreign function
directly.
In other words
foreign export dynamic exp :: (Int -> IO Int) -> IO Addr
is equivalent to
exp :: (Int -> IO Int) -> Addr
exp f = exp' =<< newStablePtr f
foreign import exp' :: StablePtr (Int -> IO Int) -> IO Addr
-- exp' generated by the Haskell compiler.
> Unless you're arguing that, since it brings a name into scope it
> can be thought of as a kind of import??? (But I don't think you
> are saying that.)
I am!
--
__("< Marcin Kowalczyk * [EMAIL PROTECTED] http://qrczak.ids.net.pl/
\__/
^^ SYGNATURA ZASTĘPCZA
QRCZAK
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