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It is very convenient to have operators which return the “minimum” or the “maximum” of two arguments. In GNU C++ (but not in GNU C),
<?
b>?
bThese operations are not primitive in ordinary C++, since you can use a macro to return the minimum of two things in C++, as in the following example.
#define MIN(X,Y) ((X) < (Y) ? : (X) : (Y))
You might then use int min = MIN (i, j); to set min to the minimum value of variables i and j.
However, side effects in X
or Y
may cause unintended behavior. For example, MIN (i++, j++)
will fail, incrementing the smaller counter twice. The GNU C typeof
extension allows you to write safe macros that avoid this kind of problem (see Typeof). However, writing MIN
and MAX
as macros also forces you to use function-call notation for a fundamental arithmetic operation. Using GNU C++ extensions, you can write int min = i <? j;
instead.
Since <?
and >?
are built into the compiler, they properly handle expressions with side-effects; int min = i++ <? j++;
works correctly.