...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
template <class T>
struct is_enum : public true_type-or-false_type
{};
Inherits: If T is a (possibly cv-qualified) enum type then inherits from true_type, otherwise inherits from false_type.
C++ Standard Reference: 3.9.2 and 7.2.
Header: #include
<boost/type_traits/is_enum.hpp>
or #include <boost/type_traits.hpp>
Compiler Compatibility: Requires a correctly functioning is_convertible template; this means that is_enum is currently broken under Borland C++ Builder 5, and for the Metrowerks compiler prior to version 8, other compilers should handle this template just fine.
Examples:
Given:
enum my_enum { one, two };
is_enum<my_enum>
inherits fromtrue_type
.
is_enum<my_enum const>::type
is the typetrue_type
.
is_enum<my_enum>::value
is an integral constant expression that evaluates to true.
is_enum<my_enum&>::value
is an integral constant expression that evaluates to false.
is_enum<my_enum*>::value
is an integral constant expression that evaluates to false.
is_enum<T>::value_type
is the typebool
.