C pet peeve - (nf)

tektronix!tekecs!randals tektronix!tekecs!randals
Sat Mar 26 17:54:42 AEST 1983

In a recent article from:

	Bill Lee
	lee at utexas-11

he indicates that the way to get unions without the additional
level of indirection is to do something like:

	#define as_int o.as_int1;
	#define as_ptr o.as_ptr1;

	struct foo {
		short type;
		union {
			int as_int1;
			char *as_ptr1;
		} o;
	} bar;

DON'T APPEND the semicolon to the definition!!  If you refer
to bar.as_int, you will get (expanded) "bar.o.as_int1;", which
will undoubtedly botch the compile (an extra semicolon).

Remember, #define's are *not* "C" code... they are simply
straight substitutions!  Make them look like this:

	#define as_int o.as_int1
	#define as_ptr o.as_ptr1

Randal L. ("sometimes below C-level") Schwartz
Tektronix Engineering Computing Systems (the UNIX folks)
Wilsonville, Oregon, USA

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