do{} while (0)

[flyingxu]

I see some MFC macro use do{}while(0), for example #define AfxOutputDebugString(lpsz) \ do \ { \ USES_CONVERSION; \ _RPT0(_CRT_WARN, W2CA(lpsz)); \ } while (0) #else why use this kind of technique?

[Maxwell Chen]

Not anymore! Now AfxOutputDebugstring is defined as:

#define AfxOutputDebugString TRACE

Maxwell Chen

[BadKarma]

Hi, the do{} while(0) is a technique to force the programmer to place a ; after the MACRO line so it looks more like a normal function then a macro

codito ergo sum

[flyingxu]

GREAT! it makes sense.