initial checkin of mapbox::util::variant
This commit is contained in:
Dennis Luxen
parent
7d2c627ad2
commit
e2794e9f06
127
ThirdParty/variant/recursive_wrapper.hpp
vendored
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127
ThirdParty/variant/recursive_wrapper.hpp
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@ -0,0 +1,127 @@
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#ifndef MAPBOX_UTIL_VARIANT_RECURSIVE_WRAPPER_HPP
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#define MAPBOX_UTIL_VARIANT_RECURSIVE_WRAPPER_HPP
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#include <utility>
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namespace mapbox { namespace util {
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template <typename T>
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class recursive_wrapper
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{
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public:
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using type = T;
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private:
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T* p_;
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public:
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~recursive_wrapper();
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recursive_wrapper();
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recursive_wrapper(recursive_wrapper const& operand);
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recursive_wrapper(T const& operand);
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recursive_wrapper(recursive_wrapper&& operand);
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recursive_wrapper(T&& operand);
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private:
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void assign(const T& rhs);
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public:
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inline recursive_wrapper& operator=(recursive_wrapper const& rhs)
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{
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assign( rhs.get() );
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return *this;
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}
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inline recursive_wrapper& operator=(T const& rhs)
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{
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assign( rhs );
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return *this;
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}
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inline void swap(recursive_wrapper& operand) noexcept
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{
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T* temp = operand.p_;
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operand.p_ = p_;
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p_ = temp;
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}
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recursive_wrapper& operator=(recursive_wrapper&& rhs) noexcept
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{
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swap(rhs);
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return *this;
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}
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recursive_wrapper& operator=(T&& rhs)
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{
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get() = std::move(rhs);
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return *this;
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}
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public:
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T& get() { return *get_pointer(); }
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const T& get() const { return *get_pointer(); }
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T* get_pointer() { return p_; }
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const T* get_pointer() const { return p_; }
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operator T const&() const { return this->get(); }
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operator T&() { return this->get(); }
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};
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template <typename T>
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recursive_wrapper<T>::~recursive_wrapper()
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{
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delete p_;
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}
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template <typename T>
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recursive_wrapper<T>::recursive_wrapper()
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: p_(new T)
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{
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}
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template <typename T>
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recursive_wrapper<T>::recursive_wrapper(recursive_wrapper const& operand)
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: p_(new T( operand.get() ))
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{
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}
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template <typename T>
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recursive_wrapper<T>::recursive_wrapper(T const& operand)
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: p_(new T(operand))
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{
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}
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template <typename T>
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recursive_wrapper<T>::recursive_wrapper(recursive_wrapper&& operand)
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: p_(operand.p_)
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{
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operand.p_ = nullptr;
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}
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template <typename T>
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recursive_wrapper<T>::recursive_wrapper(T&& operand)
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: p_(new T( std::move(operand) ))
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{
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}
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template <typename T>
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void recursive_wrapper<T>::assign(const T& rhs)
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{
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this->get() = rhs;
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}
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template <typename T>
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inline void swap(recursive_wrapper<T>& lhs, recursive_wrapper<T>& rhs) noexcept
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{
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lhs.swap(rhs);
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}
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}}
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#endif // MAPBOX_UTIL_VARIANT_RECURSIVE_WRAPPER_HPP
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731
ThirdParty/variant/variant.hpp
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731
ThirdParty/variant/variant.hpp
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@ -0,0 +1,731 @@
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#ifndef MAPBOX_UTIL_VARIANT_HPP
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#define MAPBOX_UTIL_VARIANT_HPP
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#include <utility>
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#include <typeinfo>
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#include <type_traits>
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#include <algorithm> // std::move/swap
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#include <stdexcept> // runtime_error
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#include <new> // operator new
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#include <cstddef> // size_t
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#include <iosfwd>
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#include <string>
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#include "recursive_wrapper.hpp"
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#ifdef _MSC_VER
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// http://msdn.microsoft.com/en-us/library/z8y1yy88.aspx
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#ifdef NDEBUG
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#define VARIANT_INLINE __forceinline
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#else
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#define VARIANT_INLINE __declspec(noinline)
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#endif
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#else
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#ifdef NDEBUG
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#define VARIANT_INLINE inline __attribute__((always_inline))
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#else
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#define VARIANT_INLINE __attribute__((noinline))
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#endif
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#endif
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#define VARIANT_MAJOR_VERSION 0
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#define VARIANT_MINOR_VERSION 1
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#define VARIANT_PATCH_VERSION 0
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// translates to 100
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#define VARIANT_VERSION (VARIANT_MAJOR_VERSION*100000) + (VARIANT_MINOR_VERSION*100) + (VARIANT_PATCH_VERSION)
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namespace mapbox { namespace util { namespace detail {
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static constexpr std::size_t invalid_value = std::size_t(-1);
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template <typename T, typename...Types>
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struct direct_type;
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template <typename T, typename First, typename...Types>
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struct direct_type<T, First, Types...>
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{
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static constexpr std::size_t index = std::is_same<T, First>::value
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? sizeof...(Types) : direct_type<T, Types...>::index;
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};
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template <typename T>
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struct direct_type<T>
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{
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static constexpr std::size_t index = invalid_value;
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};
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template <typename T, typename...Types>
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struct convertible_type;
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template <typename T, typename First, typename...Types>
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struct convertible_type<T, First, Types...>
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{
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static constexpr std::size_t index = std::is_convertible<T, First>::value
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? sizeof...(Types) : convertible_type<T, Types...>::index;
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};
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template <typename T>
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struct convertible_type<T>
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{
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static constexpr std::size_t index = invalid_value;
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};
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template <typename T, typename...Types>
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struct value_traits
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{
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static constexpr std::size_t direct_index = direct_type<T, Types...>::index;
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static constexpr std::size_t index =
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(direct_index == invalid_value) ? convertible_type<T, Types...>::index : direct_index;
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};
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template <typename T, typename...Types>
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struct is_valid_type;
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template <typename T, typename First, typename... Types>
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struct is_valid_type<T, First, Types...>
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{
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static constexpr bool value = std::is_convertible<T, First>::value
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|| is_valid_type<T, Types...>::value;
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};
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template <typename T>
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struct is_valid_type<T> : std::false_type {};
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template <std::size_t N, typename ... Types>
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struct select_type
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{
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static_assert(N < sizeof...(Types), "index out of bounds");
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};
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template <std::size_t N, typename T, typename ... Types>
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struct select_type<N, T, Types...>
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{
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using type = typename select_type<N - 1, Types...>::type;
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};
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template <typename T, typename ... Types>
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struct select_type<0, T, Types...>
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{
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using type = T;
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};
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} // namespace detail
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// static visitor
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template <typename R = void>
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struct static_visitor
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{
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using result_type = R;
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protected:
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static_visitor() {}
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~static_visitor() {}
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};
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template <std::size_t arg1, std::size_t ... others>
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struct static_max;
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template <std::size_t arg>
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struct static_max<arg>
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{
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static const std::size_t value = arg;
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};
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template <std::size_t arg1, std::size_t arg2, std::size_t ... others>
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struct static_max<arg1, arg2, others...>
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{
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static const std::size_t value = arg1 >= arg2 ? static_max<arg1, others...>::value :
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static_max<arg2, others...>::value;
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};
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template<typename... Types>
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struct variant_helper;
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template<typename T, typename... Types>
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struct variant_helper<T, Types...>
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{
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VARIANT_INLINE static void destroy(const std::size_t id, void * data)
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{
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if (id == sizeof...(Types))
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{
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reinterpret_cast<T*>(data)->~T();
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}
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else
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{
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variant_helper<Types...>::destroy(id, data);
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}
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}
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VARIANT_INLINE static void move(const std::size_t old_id, void * old_value, void * new_value)
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{
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if (old_id == sizeof...(Types))
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{
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new (new_value) T(std::move(*reinterpret_cast<T*>(old_value)));
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//std::memcpy(new_value, old_value, sizeof(T));
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// ^^ DANGER: this should only be considered for relocatable types e.g built-in types
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// Also, I don't see any measurable performance benefit just yet
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}
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else
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{
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variant_helper<Types...>::move(old_id, old_value, new_value);
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}
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}
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VARIANT_INLINE static void copy(const std::size_t old_id, const void * old_value, void * new_value)
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{
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if (old_id == sizeof...(Types))
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{
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new (new_value) T(*reinterpret_cast<const T*>(old_value));
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}
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else
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{
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variant_helper<Types...>::copy(old_id, old_value, new_value);
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}
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}
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};
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template<> struct variant_helper<>
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{
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VARIANT_INLINE static void destroy(const std::size_t, void *) {}
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VARIANT_INLINE static void move(const std::size_t, void *, void *) {}
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VARIANT_INLINE static void copy(const std::size_t, const void *, void *) {}
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};
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namespace detail {
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template <typename T>
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struct unwrapper
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{
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T const& operator() (T const& obj) const
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{
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return obj;
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}
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T& operator() (T & obj) const
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{
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return obj;
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}
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};
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template <typename T>
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struct unwrapper<recursive_wrapper<T>>
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{
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auto operator() (recursive_wrapper<T> const& obj) const
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-> typename recursive_wrapper<T>::type const&
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{
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return obj.get();
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}
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};
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template <typename F, typename V, typename...Types>
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struct dispatcher;
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template <typename F, typename V, typename T, typename...Types>
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struct dispatcher<F, V, T, Types...>
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{
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using result_type = typename F::result_type;
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VARIANT_INLINE static result_type apply_const(V const& v, F f)
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{
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if (v.get_type_index() == sizeof...(Types))
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{
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return f(unwrapper<T>()(v. template get<T>()));
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}
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else
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{
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return dispatcher<F, V, Types...>::apply_const(v, f);
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}
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}
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VARIANT_INLINE static result_type apply(V & v, F f)
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{
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if (v.get_type_index() == sizeof...(Types))
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{
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return f(unwrapper<T>()(v. template get<T>()));
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}
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else
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{
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return dispatcher<F, V, Types...>::apply(v, f);
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}
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}
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};
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template<typename F, typename V>
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struct dispatcher<F, V>
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{
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using result_type = typename F::result_type;
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VARIANT_INLINE static result_type apply_const(V const&, F)
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{
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throw std::runtime_error(std::string("unary dispatch: FAIL ") + typeid(V).name());
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}
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VARIANT_INLINE static result_type apply(V &, F)
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{
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throw std::runtime_error(std::string("unary dispatch: FAIL ") + typeid(V).name());
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}
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};
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template <typename F, typename V, typename T, typename...Types>
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struct binary_dispatcher_rhs;
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template <typename F, typename V, typename T0, typename T1, typename...Types>
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struct binary_dispatcher_rhs<F, V, T0, T1, Types...>
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{
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using result_type = typename F::result_type;
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VARIANT_INLINE static result_type apply_const(V const& lhs, V const& rhs, F f)
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{
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if (rhs.get_type_index() == sizeof...(Types)) // call binary functor
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{
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return f(unwrapper<T0>()(lhs. template get<T0>()),
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unwrapper<T1>()(rhs. template get<T1>()));
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}
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else
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{
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return binary_dispatcher_rhs<F, V, T0, Types...>::apply_const(lhs, rhs, f);
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}
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}
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VARIANT_INLINE static result_type apply(V & lhs, V & rhs, F f)
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{
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if (rhs.get_type_index() == sizeof...(Types)) // call binary functor
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{
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return f(unwrapper<T0>()(lhs. template get<T0>()),
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unwrapper<T1>()(rhs. template get<T1>()));
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}
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else
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{
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return binary_dispatcher_rhs<F, V, T0, Types...>::apply(lhs, rhs, f);
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}
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}
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};
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template<typename F, typename V, typename T>
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struct binary_dispatcher_rhs<F, V, T>
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{
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using result_type = typename F::result_type;
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VARIANT_INLINE static result_type apply_const(V const&, V const&, F)
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{
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throw std::runtime_error("binary dispatch: FAIL");
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}
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VARIANT_INLINE static result_type apply(V &, V &, F)
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{
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throw std::runtime_error("binary dispatch: FAIL");
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}
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};
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template <typename F, typename V, typename T, typename...Types>
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struct binary_dispatcher_lhs;
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template <typename F, typename V, typename T0, typename T1, typename...Types>
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struct binary_dispatcher_lhs<F, V, T0, T1, Types...>
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{
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using result_type = typename F::result_type;
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VARIANT_INLINE static result_type apply_const(V const& lhs, V const& rhs, F f)
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{
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if (lhs.get_type_index() == sizeof...(Types)) // call binary functor
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{
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return f(lhs. template get<T1>(), rhs. template get<T0>());
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}
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else
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{
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return binary_dispatcher_lhs<F, V, T0, Types...>::apply_const(lhs, rhs, f);
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}
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}
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VARIANT_INLINE static result_type apply(V & lhs, V & rhs, F f)
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{
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if (lhs.get_type_index() == sizeof...(Types)) // call binary functor
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{
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return f(lhs. template get<T1>(), rhs. template get<T0>());
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}
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else
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{
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return binary_dispatcher_lhs<F, V, T0, Types...>::apply(lhs, rhs, f);
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}
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}
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};
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template<typename F, typename V, typename T>
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struct binary_dispatcher_lhs<F, V, T>
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{
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using result_type = typename F::result_type;
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VARIANT_INLINE static result_type apply_const(V const&, V const&, F)
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{
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throw std::runtime_error("binary dispatch: FAIL");
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}
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VARIANT_INLINE static result_type apply(V &, V &, F)
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{
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throw std::runtime_error("binary dispatch: FAIL");
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}
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};
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template <typename F, typename V, typename...Types>
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struct binary_dispatcher;
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template <typename F, typename V, typename T, typename...Types>
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struct binary_dispatcher<F, V, T, Types...>
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{
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using result_type = typename F::result_type;
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VARIANT_INLINE static result_type apply_const(V const& v0, V const& v1, F f)
|
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{
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if (v0.get_type_index() == sizeof...(Types))
|
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{
|
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if (v0.get_type_index() == v1.get_type_index())
|
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{
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return f(v0. template get<T>(), v1. template get<T>()); // call binary functor
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}
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else
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{
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return binary_dispatcher_rhs<F, V, T, Types...>::apply_const(v0, v1, f);
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}
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}
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else if (v1.get_type_index() == sizeof...(Types))
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{
|
||||
return binary_dispatcher_lhs<F, V, T, Types...>::apply_const(v0, v1, f);
|
||||
}
|
||||
return binary_dispatcher<F, V, Types...>::apply_const(v0, v1, f);
|
||||
}
|
||||
|
||||
VARIANT_INLINE static result_type apply(V & v0, V & v1, F f)
|
||||
{
|
||||
if (v0.get_type_index() == sizeof...(Types))
|
||||
{
|
||||
if (v0.get_type_index() == v1.get_type_index())
|
||||
{
|
||||
return f(v0. template get<T>(), v1. template get<T>()); // call binary functor
|
||||
}
|
||||
else
|
||||
{
|
||||
return binary_dispatcher_rhs<F, V, T, Types...>::apply(v0, v1, f);
|
||||
}
|
||||
}
|
||||
else if (v1.get_type_index() == sizeof...(Types))
|
||||
{
|
||||
return binary_dispatcher_lhs<F, V, T, Types...>::apply(v0, v1, f);
|
||||
}
|
||||
return binary_dispatcher<F, V, Types...>::apply(v0, v1, f);
|
||||
}
|
||||
};
|
||||
|
||||
template<typename F, typename V>
|
||||
struct binary_dispatcher<F, V>
|
||||
{
|
||||
using result_type = typename F::result_type;
|
||||
VARIANT_INLINE static result_type apply_const(V const&, V const&, F)
|
||||
{
|
||||
throw std::runtime_error("binary dispatch: FAIL");
|
||||
}
|
||||
|
||||
VARIANT_INLINE static result_type apply(V &, V &, F)
|
||||
{
|
||||
throw std::runtime_error("binary dispatch: FAIL");
|
||||
}
|
||||
};
|
||||
|
||||
// comparator functors
|
||||
struct equal_comp
|
||||
{
|
||||
template <typename T>
|
||||
bool operator()(T const& lhs, T const& rhs) const
|
||||
{
|
||||
return lhs == rhs;
|
||||
}
|
||||
};
|
||||
|
||||
struct less_comp
|
||||
{
|
||||
template <typename T>
|
||||
bool operator()(T const& lhs, T const& rhs) const
|
||||
{
|
||||
return lhs < rhs;
|
||||
}
|
||||
};
|
||||
|
||||
template <typename Variant, typename Comp>
|
||||
class comparer : public static_visitor<bool>
|
||||
{
|
||||
public:
|
||||
explicit comparer(Variant const& lhs) noexcept
|
||||
: lhs_(lhs) {}
|
||||
comparer& operator=(comparer const&) = delete;
|
||||
// visitor
|
||||
template<typename T>
|
||||
bool operator()(T const& rhs_content) const
|
||||
{
|
||||
T const& lhs_content = lhs_.template get<T>();
|
||||
return Comp()(lhs_content, rhs_content);
|
||||
}
|
||||
private:
|
||||
Variant const& lhs_;
|
||||
};
|
||||
|
||||
// operator<< helper
|
||||
template <typename Out>
|
||||
class printer : public static_visitor<>
|
||||
{
|
||||
public:
|
||||
explicit printer(Out & out)
|
||||
: out_(out) {}
|
||||
printer& operator=(printer const&) = delete;
|
||||
|
||||
// visitor
|
||||
template <typename T>
|
||||
void operator()(T const& operand) const
|
||||
{
|
||||
out_ << operand;
|
||||
}
|
||||
private:
|
||||
Out & out_;
|
||||
};
|
||||
|
||||
} // namespace detail
|
||||
|
||||
template<typename... Types>
|
||||
class variant
|
||||
{
|
||||
private:
|
||||
|
||||
static const std::size_t data_size = static_max<sizeof(Types)...>::value;
|
||||
static const std::size_t data_align = static_max<alignof(Types)...>::value;
|
||||
|
||||
using data_type = typename std::aligned_storage<data_size, data_align>::type;
|
||||
using helper_type = variant_helper<Types...>;
|
||||
|
||||
std::size_t type_index;
|
||||
data_type data;
|
||||
|
||||
public:
|
||||
|
||||
VARIANT_INLINE variant()
|
||||
: type_index(sizeof...(Types) - 1)
|
||||
{
|
||||
new (&data) typename detail::select_type<0, Types...>::type();
|
||||
}
|
||||
|
||||
template <typename T, class = typename std::enable_if<
|
||||
detail::is_valid_type<T, Types...>::value>::type>
|
||||
VARIANT_INLINE explicit variant(T const& val) noexcept
|
||||
: type_index(detail::value_traits<T, Types...>::index)
|
||||
{
|
||||
constexpr std::size_t index = sizeof...(Types) - detail::value_traits<T, Types...>::index - 1;
|
||||
using target_type = typename detail::select_type<index, Types...>::type;
|
||||
new (&data) target_type(val);
|
||||
}
|
||||
|
||||
template <typename T, class = typename std::enable_if<
|
||||
detail::is_valid_type<T, Types...>::value>::type>
|
||||
VARIANT_INLINE variant(T && val) noexcept
|
||||
: type_index(detail::value_traits<T, Types...>::index)
|
||||
{
|
||||
constexpr std::size_t index = sizeof...(Types) - detail::value_traits<T, Types...>::index - 1;
|
||||
using target_type = typename detail::select_type<index, Types...>::type;
|
||||
new (&data) target_type(std::forward<T>(val)); // nothrow
|
||||
}
|
||||
|
||||
VARIANT_INLINE variant(variant<Types...> const& old)
|
||||
: type_index(old.type_index)
|
||||
{
|
||||
helper_type::copy(old.type_index, &old.data, &data);
|
||||
}
|
||||
|
||||
VARIANT_INLINE variant(variant<Types...>&& old) noexcept
|
||||
: type_index(old.type_index)
|
||||
{
|
||||
helper_type::move(old.type_index, &old.data, &data);
|
||||
}
|
||||
|
||||
friend void swap(variant<Types...> & first, variant<Types...> & second)
|
||||
{
|
||||
using std::swap; //enable ADL
|
||||
swap(first.type_index, second.type_index);
|
||||
swap(first.data, second.data);
|
||||
}
|
||||
|
||||
VARIANT_INLINE variant<Types...>& operator=(variant<Types...> other)
|
||||
{
|
||||
swap(*this, other);
|
||||
return *this;
|
||||
}
|
||||
|
||||
// conversions
|
||||
// move-assign
|
||||
template <typename T>
|
||||
VARIANT_INLINE variant<Types...>& operator=(T && rhs) noexcept
|
||||
{
|
||||
variant<Types...> temp(std::move(rhs));
|
||||
swap(*this, temp);
|
||||
return *this;
|
||||
}
|
||||
|
||||
// copy-assign
|
||||
template <typename T>
|
||||
VARIANT_INLINE variant<Types...>& operator=(T const& rhs)
|
||||
{
|
||||
variant<Types...> temp(rhs);
|
||||
swap(*this, temp);
|
||||
return *this;
|
||||
}
|
||||
|
||||
template<typename T>
|
||||
VARIANT_INLINE bool is() const
|
||||
{
|
||||
return (type_index == detail::direct_type<T, Types...>::index);
|
||||
}
|
||||
|
||||
VARIANT_INLINE bool valid() const
|
||||
{
|
||||
return (type_index != detail::invalid_value);
|
||||
}
|
||||
|
||||
template<typename T, typename... Args>
|
||||
VARIANT_INLINE void set(Args&&... args)
|
||||
{
|
||||
helper_type::destroy(type_index, &data);
|
||||
new (&data) T(std::forward<Args>(args)...);
|
||||
type_index = detail::direct_type<T, Types...>::index;
|
||||
}
|
||||
|
||||
template<typename T>
|
||||
VARIANT_INLINE T& get()
|
||||
{
|
||||
if (type_index == detail::direct_type<T, Types...>::index)
|
||||
{
|
||||
return *reinterpret_cast<T*>(&data);
|
||||
}
|
||||
else
|
||||
{
|
||||
throw std::runtime_error("in get()");
|
||||
}
|
||||
}
|
||||
|
||||
template<typename T>
|
||||
VARIANT_INLINE T const& get() const
|
||||
{
|
||||
if (type_index == detail::direct_type<T, Types...>::index)
|
||||
{
|
||||
return *reinterpret_cast<T const*>(&data);
|
||||
}
|
||||
else
|
||||
{
|
||||
throw std::runtime_error("in get()");
|
||||
}
|
||||
}
|
||||
|
||||
VARIANT_INLINE std::size_t get_type_index() const
|
||||
{
|
||||
return type_index;
|
||||
}
|
||||
|
||||
// visitor
|
||||
// unary
|
||||
template <typename F, typename V>
|
||||
auto VARIANT_INLINE
|
||||
static visit(V const& v, F f)
|
||||
-> decltype(detail::dispatcher<F, V, Types...>::apply_const(v, f))
|
||||
{
|
||||
return detail::dispatcher<F, V, Types...>::apply_const(v, f);
|
||||
}
|
||||
// non-const
|
||||
template <typename F, typename V>
|
||||
auto VARIANT_INLINE
|
||||
static visit(V & v, F f)
|
||||
-> decltype(detail::dispatcher<F, V, Types...>::apply(v, f))
|
||||
{
|
||||
return detail::dispatcher<F, V, Types...>::apply(v, f);
|
||||
}
|
||||
|
||||
// binary
|
||||
// const
|
||||
template <typename F, typename V>
|
||||
auto VARIANT_INLINE
|
||||
static binary_visit(V const& v0, V const& v1, F f)
|
||||
-> decltype(detail::binary_dispatcher<F, V, Types...>::apply_const(v0, v1, f))
|
||||
{
|
||||
return detail::binary_dispatcher<F, V, Types...>::apply_const(v0, v1, f);
|
||||
}
|
||||
// non-const
|
||||
template <typename F, typename V>
|
||||
auto VARIANT_INLINE
|
||||
static binary_visit(V& v0, V& v1, F f)
|
||||
-> decltype(detail::binary_dispatcher<F, V, Types...>::apply(v0, v1, f))
|
||||
{
|
||||
return detail::binary_dispatcher<F, V, Types...>::apply(v0, v1, f);
|
||||
}
|
||||
|
||||
~variant() noexcept
|
||||
{
|
||||
helper_type::destroy(type_index, &data);
|
||||
}
|
||||
|
||||
// comparison operators
|
||||
// equality
|
||||
VARIANT_INLINE bool operator==(variant const& rhs) const
|
||||
{
|
||||
if (this->get_type_index() != rhs.get_type_index())
|
||||
return false;
|
||||
detail::comparer<variant, detail::equal_comp> visitor(*this);
|
||||
return visit(rhs, visitor);
|
||||
}
|
||||
// less than
|
||||
VARIANT_INLINE bool operator<(variant const& rhs) const
|
||||
{
|
||||
if (this->get_type_index() != rhs.get_type_index())
|
||||
{
|
||||
return this->get_type_index() < rhs.get_type_index();
|
||||
// ^^ borrowed from boost::variant
|
||||
}
|
||||
detail::comparer<variant, detail::less_comp> visitor(*this);
|
||||
return visit(rhs, visitor);
|
||||
}
|
||||
};
|
||||
|
||||
// unary visitor interface
|
||||
|
||||
// const
|
||||
template <typename V, typename F>
|
||||
auto VARIANT_INLINE static apply_visitor(F f, V const& v) -> decltype(V::visit(v, f))
|
||||
{
|
||||
return V::visit(v, f);
|
||||
}
|
||||
// non-const
|
||||
template <typename V, typename F>
|
||||
auto VARIANT_INLINE static apply_visitor(F f, V & v) -> decltype(V::visit(v, f))
|
||||
{
|
||||
return V::visit(v, f);
|
||||
}
|
||||
|
||||
// binary visitor interface
|
||||
// const
|
||||
template <typename V, typename F>
|
||||
auto VARIANT_INLINE static apply_visitor(F f, V const& v0, V const& v1) -> decltype(V::binary_visit(v0, v1, f))
|
||||
{
|
||||
return V::binary_visit(v0, v1, f);
|
||||
}
|
||||
// non-const
|
||||
template <typename V, typename F>
|
||||
auto VARIANT_INLINE static apply_visitor(F f, V & v0, V & v1) -> decltype(V::binary_visit(v0, v1, f))
|
||||
{
|
||||
return V::binary_visit(v0, v1, f);
|
||||
}
|
||||
|
||||
|
||||
// operator<<
|
||||
template <typename charT, typename traits, typename Variant>
|
||||
VARIANT_INLINE std::basic_ostream<charT, traits>&
|
||||
operator<< (std::basic_ostream<charT, traits>& out, Variant const& rhs)
|
||||
{
|
||||
detail::printer<std::basic_ostream<charT, traits>> visitor(out);
|
||||
apply_visitor(visitor, rhs);
|
||||
return out;
|
||||
}
|
||||
|
||||
}}
|
||||
|
||||
#endif // MAPBOX_UTIL_VARIANT_HPP
|
||||
Loading…
Reference in New Issue
Block a user