Server : Apache/2.4.41 (Ubuntu) System : Linux absol.cf 5.4.0-198-generic #218-Ubuntu SMP Fri Sep 27 20:18:53 UTC 2024 x86_64 User : www-data ( 33) PHP Version : 7.4.33 Disable Function : pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_get_handler,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,pcntl_async_signals,pcntl_unshare, Directory : /usr/include/boost/histogram/axis/
Upload File :
Current File : //usr/include/boost/histogram/axis/variant.hpp
// Copyright 2015-2017 Hans Dembinski
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt
// or copy at http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_HISTOGRAM_AXIS_VARIANT_HPP
#define BOOST_HISTOGRAM_AXIS_VARIANT_HPP
#include <boost/histogram/axis/iterator.hpp>
#include <boost/histogram/axis/polymorphic_bin.hpp>
#include <boost/histogram/axis/traits.hpp>
#include <boost/histogram/detail/cat.hpp>
#include <boost/histogram/detail/relaxed_equal.hpp>
#include <boost/histogram/detail/static_if.hpp>
#include <boost/histogram/detail/type_name.hpp>
#include <boost/histogram/fwd.hpp>
#include <boost/mp11/function.hpp>
#include <boost/mp11/list.hpp>
#include <boost/mp11/utility.hpp>
#include <boost/throw_exception.hpp>
#include <boost/variant2/variant.hpp>
#include <ostream>
#include <stdexcept>
#include <type_traits>
#include <utility>
namespace boost {
namespace histogram {
namespace axis {
/// Polymorphic axis type
template <class... Ts>
class variant : public iterator_mixin<variant<Ts...>> {
using impl_type = boost::variant2::variant<Ts...>;
template <class T>
using is_bounded_type = mp11::mp_contains<variant, std::decay_t<T>>;
template <typename T>
using requires_bounded_type = std::enable_if_t<is_bounded_type<T>::value>;
// maybe metadata_type or const metadata_type, if bounded type is const
using metadata_type = std::remove_reference_t<decltype(
traits::metadata(std::declval<std::remove_pointer_t<mp11::mp_first<variant>>>()))>;
public:
// cannot import ctors with using directive, it breaks gcc and msvc
variant() = default;
variant(const variant&) = default;
variant& operator=(const variant&) = default;
variant(variant&&) = default;
variant& operator=(variant&&) = default;
template <class T, class = requires_bounded_type<T>>
variant(T&& t) : impl(std::forward<T>(t)) {}
template <class T, class = requires_bounded_type<T>>
variant& operator=(T&& t) {
impl = std::forward<T>(t);
return *this;
}
template <class... Us>
variant(const variant<Us...>& u) {
this->operator=(u);
}
template <class... Us>
variant& operator=(const variant<Us...>& u) {
visit(
[this](const auto& u) {
using U = std::decay_t<decltype(u)>;
detail::static_if<is_bounded_type<U>>(
[this](const auto& u) { this->operator=(u); },
[](const auto&) {
BOOST_THROW_EXCEPTION(std::runtime_error(detail::cat(
detail::type_name<U>(), " is not convertible to a bounded type of ",
detail::type_name<variant>())));
},
u);
},
u);
return *this;
}
/// Return size of axis.
index_type size() const {
return visit([](const auto& a) { return a.size(); }, *this);
}
/// Return options of axis or option::none_t if axis has no options.
unsigned options() const {
return visit([](const auto& a) { return axis::traits::options(a); }, *this);
}
/// Return reference to const metadata or instance of null_type if axis has no
/// metadata.
const metadata_type& metadata() const {
return visit(
[](const auto& a) -> const metadata_type& {
using M = decltype(traits::metadata(a));
return detail::static_if<std::is_same<M, const metadata_type&>>(
[](const auto& a) -> const metadata_type& { return traits::metadata(a); },
[](const auto&) -> const metadata_type& {
BOOST_THROW_EXCEPTION(std::runtime_error(
detail::cat("cannot return metadata of type ", detail::type_name<M>(),
" through axis::variant interface which uses type ",
detail::type_name<metadata_type>(),
"; use boost::histogram::axis::get to obtain a reference "
"of this axis type")));
},
a);
},
*this);
}
/// Return reference to metadata or instance of null_type if axis has no
/// metadata.
metadata_type& metadata() {
return visit(
[](auto& a) -> metadata_type& {
using M = decltype(traits::metadata(a));
return detail::static_if<std::is_same<M, metadata_type&>>(
[](auto& a) -> metadata_type& { return traits::metadata(a); },
[](auto&) -> metadata_type& {
BOOST_THROW_EXCEPTION(std::runtime_error(
detail::cat("cannot return metadata of type ", detail::type_name<M>(),
" through axis::variant interface which uses type ",
detail::type_name<metadata_type>(),
"; use boost::histogram::axis::get to obtain a reference "
"of this axis type")));
},
a);
},
*this);
}
/** Return index for value argument.
Throws std::invalid_argument if axis has incompatible call signature.
*/
template <class U>
index_type index(const U& u) const {
return visit([&u](const auto& a) { return traits::index(a, u); }, *this);
}
/** Return value for index argument.
Only works for axes with value method that returns something convertible
to double and will throw a runtime_error otherwise, see
axis::traits::value().
*/
double value(real_index_type idx) const {
return visit([idx](const auto& a) { return traits::value_as<double>(a, idx); },
*this);
}
/** Return bin for index argument.
Only works for axes with value method that returns something convertible
to double and will throw a runtime_error otherwise, see
axis::traits::value().
*/
auto bin(index_type idx) const {
return visit(
[idx](const auto& a) {
return detail::value_method_switch(
[idx](const auto& a) { // axis is discrete
const double x = traits::value_as<double>(a, idx);
return polymorphic_bin<double>(x, x);
},
[idx](const auto& a) { // axis is continuous
const double x1 = traits::value_as<double>(a, idx);
const double x2 = traits::value_as<double>(a, idx + 1);
return polymorphic_bin<double>(x1, x2);
},
a);
},
*this);
}
/** Compare two variants.
Return true if the variants point to the same concrete axis type and the types compare
equal. Otherwise return false.
*/
template <class... Us>
bool operator==(const variant<Us...>& u) const {
return visit([&u](const auto& x) { return u == x; }, *this);
}
/** Compare variant with a concrete axis type.
Return true if the variant point to the same concrete axis type and the types compare
equal. Otherwise return false.
*/
template <class T>
bool operator==(const T& t) const {
return detail::static_if_c<(mp11::mp_contains<impl_type, T>::value ||
mp11::mp_contains<impl_type, T*>::value ||
mp11::mp_contains<impl_type, const T*>::value)>(
[&](const auto& t) {
using U = std::decay_t<decltype(t)>;
const U* tp = detail::variant_access::template get_if<U>(this);
return tp && detail::relaxed_equal(*tp, t);
},
[&](const auto&) { return false; }, t);
}
/// The negation of operator==.
template <class T>
bool operator!=(const T& t) const {
return !operator==(t);
}
private:
impl_type impl;
friend struct detail::variant_access;
friend struct boost::histogram::unsafe_access;
};
// specialization for empty argument list, useful for meta-programming
template <>
class variant<> {};
/// Apply visitor to variant (reference).
template <class Visitor, class... Us>
decltype(auto) visit(Visitor&& vis, variant<Us...>& var) {
return detail::variant_access::visit(vis, var);
}
/// Apply visitor to variant (movable reference).
template <class Visitor, class... Us>
decltype(auto) visit(Visitor&& vis, variant<Us...>&& var) {
return detail::variant_access::visit(vis, std::move(var));
}
/// Apply visitor to variant (const reference).
template <class Visitor, class... Us>
decltype(auto) visit(Visitor&& vis, const variant<Us...>& var) {
return detail::variant_access::visit(vis, var);
}
/// Returns pointer to T in variant or null pointer if type does not match.
template <class T, class... Us>
T* get_if(variant<Us...>* v) {
return detail::variant_access::template get_if<T>(v);
}
/// Returns pointer to const T in variant or null pointer if type does not match.
template <class T, class... Us>
const T* get_if(const variant<Us...>* v) {
return detail::variant_access::template get_if<T>(v);
}
/// Return reference to T, throws std::runtime_error if type does not match.
template <class T, class... Us>
decltype(auto) get(variant<Us...>& v) {
auto tp = get_if<T>(&v);
if (!tp) BOOST_THROW_EXCEPTION(std::runtime_error("T is not the held type"));
return *tp;
}
/// Return movable reference to T, throws unspecified exception if type does not match.
template <class T, class... Us>
decltype(auto) get(variant<Us...>&& v) {
auto tp = get_if<T>(&v);
if (!tp) BOOST_THROW_EXCEPTION(std::runtime_error("T is not the held type"));
return std::move(*tp);
}
/// Return const reference to T, throws unspecified exception if type does not match.
template <class T, class... Us>
decltype(auto) get(const variant<Us...>& v) {
auto tp = get_if<T>(&v);
if (!tp) BOOST_THROW_EXCEPTION(std::runtime_error("T is not the held type"));
return *tp;
}
// pass-through version of get for generic programming
template <class T, class U>
decltype(auto) get(U&& u) {
return std::forward<U>(u);
}
// pass-through version of get_if for generic programming
template <class T, class U>
T* get_if(U* u) {
return std::is_same<T, std::decay_t<U>>::value ? reinterpret_cast<T*>(u) : nullptr;
}
// pass-through version of get_if for generic programming
template <class T, class U>
const T* get_if(const U* u) {
return std::is_same<T, std::decay_t<U>>::value ? reinterpret_cast<const T*>(u)
: nullptr;
}
} // namespace axis
} // namespace histogram
} // namespace boost
#endif
Server : Apache/2.4.41 (Ubuntu)