20 General utilities library [utilities]

20.14 Function objects [function.objects]

20.14.6 Arithmetic operations [arithmetic.operations]

20.14.6.1 Class template plus [arithmetic.operations.plus]

🔗
template<class T = void> struct plus { constexpr T operator()(const T& x, const T& y) const; };
🔗
constexpr T operator()(const T& x, const T& y) const;
1
#
Returns: x + y.
🔗
template<> struct plus<void> { template<class T, class U> constexpr auto operator()(T&& t, U&& u) const -> decltype(std::forward<T>(t) + std::forward<U>(u)); using is_transparent = unspecified; };
🔗
template<class T, class U> constexpr auto operator()(T&& t, U&& u) const -> decltype(std::forward<T>(t) + std::forward<U>(u));
2
#
Returns: std​::​forward<T>(t) + std​::​forward<U>(u).