if else define for preprocessor

Question

//initial code:

#define MYDEBUG YES

#if (defined(MYDEBUG) && MYDEBUG == YES)
#define NATIVEUNITID @"unitid_debug"
#else
#define NATIVEUNITID @"unitid_release"
#endif


//somewhere inside the code

NATIVEUNITID is @"unitid_release"

May be I do not understand something. But why? What is the proper way to define NATIVEUNITID using the other define?

I've tried both #if (MYDEBUG) and #if (MYDEBUG == true) but I obtain the same result.

Please, help me to understand this simple case. How can I receive NATIVEUNITID is @"unitid_debug" ?

Answer 1

The preprocessor cannot evaluate == for "strings".

You could retain your notation if you write #DEFINE YES 1