Getting constants from #defines

Ian Lynagh igloo at
Wed Jun 26 10:02:54 EDT 2002

On Wed, Jun 26, 2002 at 02:20:52PM +0100, Simon Marlow wrote:
> The FFI doesn't have support for grabbing the values of #defines - you need to use another tool to do this (autoconf, hsc2hs, c2hs, green-card, hdirect, whatever).

OK, I'll have a look at these.

> The declaration above binds cERR to a function of zero arguments.  i.e. in C-speak this would be 
> 	void cERR( void );
> A function of type a->b has one argument of type 'a', not zero.

OK, I thought I'd seen something of type int foo(void) given a Haskell
type () -> IO CInt, but I can't find it now so I probably imagined it.
And now I think about it I already have loads of functions whose type is
just IO something.


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