4.0 KiB
[logical.operations]
22 General utilities library [utilities]
22.10 Function objects [function.objects]
22.10.10 Logical operations [logical.operations]
22.10.10.1 General [logical.operations.general]
The library provides basic function object classes for all of the logical operators in the language ([expr.log.and], [expr.log.or], [expr.unary.op]).
22.10.10.2 Class template logical_and [logical.operations.and]
template<class T = void> struct logical_and { constexpr bool operator()(const T& x, const T& y) const; };
constexpr bool operator()(const T& x, const T& y) const;
Returns: x && y.
`template<> struct logical_and { template<class T, class U> constexpr auto operator()(T&& t, U&& u) const -> decltype(std::forward(t) && std::forward(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));
Returns: std::forward(t) && std::forward(u).
22.10.10.3 Class template logical_or [logical.operations.or]
template<class T = void> struct logical_or { constexpr bool operator()(const T& x, const T& y) const; };
constexpr bool operator()(const T& x, const T& y) const;
Returns: x || y.
`template<> struct logical_or { template<class T, class U> constexpr auto operator()(T&& t, U&& u) const -> decltype(std::forward(t) || std::forward(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));
Returns: std::forward(t) || std::forward(u).
22.10.10.4 Class template logical_not [logical.operations.not]
template<class T = void> struct logical_not { constexpr bool operator()(const T& x) const; };
constexpr bool operator()(const T& x) const;
Returns: !x.
`template<> struct logical_not { template constexpr auto operator()(T&& t) const -> decltype(!std::forward(t));
using is_transparent = unspecified; }; `
template<class T> constexpr auto operator()(T&& t) const -> decltype(!std::forward<T>(t));
Returns: !std::forward(t).