c++ - INT_[MIN|MAX] limit macros vs numeric_limits<T>

Question

Is there any argument for using the numeric limits macros (e.g. INT64_MAX) over std::numeric_limits<T>? From what I understand numeric_limits is in the standard but the macros are only in C99 so therefore non-standard.

Answer 1

The other answers mostly have correct information, but it seems that this needs updating for C++11.

In C++11, std::numeric_limits<T>::min(), std::numeric_limits<T>::max(), and std::numeric_limits<T>::lowest() are all declared constexpr, so they can be usable in most of the same contexts as INT_MIN and company. The only exception I can think of is compile-time string processing using the # stringification token.

This means that numeric_limits can be used for case labels, template parameters, etc., and you get the benefit of using it in generic code (try using INT_MIN vs. LONG_MIN in template<typename T> get_min(T t);).

C++11 also brings a solution to the issue James Kanze talks about, by adding std::numeric_limits<T>::lowest(), which gives the lowest finite value for all types, rather than the lowest value for integer types and the lowest positive value for floating-point types.