Changes between Version 45 and Version 46 of ResumedC

Timestamp:

Sep 9, 2009, 10:36:45 PM (15 years ago)

Author:

Thanatermesis

Comment:

--

ResumedC

@@ -492 +492 @@
 
 
-
+=== Macros ===
+Remember to put always the parameters between parentheses, so that maybe the parameter needs to be calculated before to use it, just like:
+{{{
+#!C
+#define MAX(a,b) ((a) > (b) ? (a) : (b))
+
+result = 2 * MAX( x, y & 0xFF );
+}}}
+
+==== The # Operator ====
+When used inside a macro, it is replaced by the parameter given to the macro call, so:
+{{{
+#!C
+#define impr(i) printf( "value " #i " = %d", i)
+
+int x = 18, y = 2;
+impr(x-y);
+// result: "value x-y = 16"
+}}}
+
+==== The ## Operator ====
+When used inside a macro, it is replaced by the parameters given to the macro and removing spaces, so:
+{{{
+#!C
+#define impr(i) printf( #var " with " #num " = %d" var ## num )
+// var ## num (x and 5) is replaced by x5
+
+int x4 = 15, x5 = 16;
+impr( x, 5 );
+// result: "x with 5 = 16"
+}}}
+
+
+==== #include, #if, #else, #elif, #endif ====
+{{{
+#!C
+#if VERSION == 1
+   #define MY_PROJ "version1.h"
+#else
+   #define MY_PROJ "version2.h"
+#endif
+
+#include MY_PROJ
+}}}
+
+
+==== #ifdef, #ifndef, #undef ====
+{{{
+#!C
+#define MAX(a,b) ((a) > (b) ? (a) : (b))
+
+#ifdef MAX
+#undef MAX
+#endif