I would recommend that you make use of the wonderful enum construct when you need to enumerate integer constants.

You should try to limit the use of #define to situations where enum can not be used - such as when you want to map a function name, a sequence of instructions, a text string or similar.

The following is nicer to use than a sequence of #define. If you do need to hard-code the mapping of symbol to integer value, then you can explicitly add a " = 1" or similar.

enum {
    actionEmpty,
    actionOn,
    actionOff,
    actionRegulate,
    actionPulse
};

Above is handled by the compiler, while below constructs are handled by the preprocessor:

#define RULE_ACTION_ON          1
#define RULE_ACTION_OFF         2
#define RULE_ACTION_REGULATE    3
#define RULE_ACTION_PULSE       4