Preprocessor command lines are used for conditional compilation of various parts of the source text depending on external conditions.
Syntax:
#ifdef identifier
Example:
#ifdef Debug
True, if the Debug identifier was defined earlier by the #define directive. Identifiers can also be defined in the Defines text box in the Script Files dialog.
Syntax:
#ifndef identifier
Example:
#ifndef Debug
Syntax:
#else
#endif
If all previous checks of #if, #ifdef, or #ifndef show the True value, then the lines from #else to #endif will be ignored during compilation.
If those checks show the False value, then the lines from the check to #else (and if #else is missing, then from the check to #endif) will be ignored.
The #endif command ends the conditional compilation.
Example:
#ifdef DEBUG printf("Location: x = %d", x); #endif
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