mikroC
making it simple...
Here is a simple example:
mikroC - C Compiler for Microchip PIC microcontrollers
//A simple macro which returns greater of its 2 arguments: #define _MAX(A, B) ((A) > (B)) ? (A) : (B)
//Let's call it:
x = _MAX(a + b, c + d);
/* Preprocessor will transform the previous line into: x = ((a + b) > (c + d)) ? (a + b) : (c + d) */
It is highly recommended to put parentheses around each of the arguments in macro body – this will avoid possible problems with operator precedence.
Undefining MacrosYou can undefine a macro using the #undef directive.
#undef macro_identifier
Directive #undef detaches any previous token sequence from the macro_identifier ; the macro definition has been forgotten, and the macro_identifier is undefined. No macro expansion occurs within #undef lines.
The state of being defined or undefined is an important property of an identifier, regardless of the actual definition. The #ifdef and #ifndef conditional direc- tives, used to test whether any identifier is currently defined or not, offer a flexible mechanism for controlling many aspects of a compilation.
After a macro identifier has been undefined, it can be redefined with #define, using the same or a different token sequence.
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