### Question 10.14

Can I use an `#ifdef` in a `#define` line, to define something two different ways?

No. You can't ``run the preprocessor on itself,'' so to speak. What you can do is use one of two completely separate `#define` lines, depending on the `#ifdef` setting.

References: ANSI Sec. 3.8.3, Sec. 3.8.3.4
ISO Sec. 6.8.3, Sec. 6.8.3.4
H&S Sec. 3.2 pp. 40-1

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