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(gcc-295.info)Min and Max

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Minimum and Maximum Operators in C++
====================================

   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),

`A <? B'
     is the "minimum", returning the smaller of the numeric values A
     and B;

`A >? B'
     is the "maximum", returning the larger of the numeric values A and
     B.

   These 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.  A GNU C extension allows you to write safe macros that
avoid this kind of problem (Note: Naming an Expression's Type.
).  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.