Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Boost
C++ Libraries
...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_signed : public true_type-or-false_type {};
Inherits: If T is an signed integer type or an enumerated type with an underlying signed integer type, then inherits from true_type, otherwise inherits from false_type.
C++ Standard Reference: 3.9.1, 7.2.
Compiler Compatibility: All current compilers are supported by this trait.
Header: #include
<boost/type_traits/is_signed.hpp>
or #include <boost/type_traits.hpp>
Examples:
is_signed<int>inherits fromtrue_type.
is_signed<int const volatile>::typeis the typetrue_type.
is_signed<unsigned int>::valueis an integral constant expression that evaluates to false.
is_signed<myclass>::valueis an integral constant expression that evaluates to false.
is_signed<char>::valueis an integral constant expression whose value depends upon the signedness of typechar.
is_signed<long long>::valueis an integral constant expression that evaluates to true.
is_signed<T>::value_typeis the typebool.