new macro to check conditions on expression macros

llimits.h

@@ -1,5 +1,5 @@
 /*
-** $Id: llimits.h,v 1.42 2002/03/26 20:46:10 roberto Exp roberto $
+** $Id: llimits.h,v 1.43 2002/04/23 14:59:35 roberto Exp roberto $
 ** Limits, basic types, and some other `installation-dependent' definitions
 ** See Copyright Notice in lua.h
 */
@@ -83,6 +83,11 @@ union L_Umaxalign { LUSER_ALIGNMENT_T u; void *s; long l; };
 #endif
 
 
+#ifndef check_exp
+#define check_exp(c,e)	(e)
+#endif
+
+
 #ifndef UNUSED
 #define UNUSED(x)	((void)(x))	/* to avoid warnings */
 #endif