Question about assertion macro

[Gregory Larkin]

Hi there,

I would like to construct an assertion macro so that I
can print the exact condition that failed as a string.

Here is the way I call the macro:

ASSERT(foo != NULL, "Unexpected NULL pointer");

And here is how it is currently defined:

#define ASSERT(relation, msg) { if(!(relation)) { \
			      printf("ASSERTION FAILED: File %s Line %d %s\n",\
                                     __FILE__, __LINE__, msg); \
			      exit(FatalError); } }

I would like to expand the macro so that I can print the message as:

ASSERTION FAILED: foo != NULL, File xxxx Line yyyy Unexpected NULL pointer

How can I print the string "foo != NULL" without passing in the test as
a string.  Can I print the test directly as a string somehow?

Thanks for any help,
-- 
Greg Larkin (ASIC Engineer)|"This is a fragile ball we are living on; 
Viewlogic Systems, Inc.    |it's a miracle and we are destroying it.."
293 Boston Post Road West  |Peter Garrett, Midnight Oil               
Marlboro, MA 01752  (greg at Viewlogic.COM)