ecency-mobile/ios/Pods/boost-for-react-native/boost/hana/bool.hpp

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/*!
@file
Defines the `Logical` and `Comparable` models of `boost::hana::integral_constant`.
@copyright Louis Dionne 2013-2016
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
*/
#ifndef BOOST_HANA_BOOL_HPP
#define BOOST_HANA_BOOL_HPP
#include <boost/hana/fwd/bool.hpp>
#include <boost/hana/concept/integral_constant.hpp>
#include <boost/hana/config.hpp>
#include <boost/hana/core/to.hpp>
#include <boost/hana/core/when.hpp>
#include <boost/hana/detail/operators/arithmetic.hpp>
#include <boost/hana/detail/operators/comparable.hpp>
#include <boost/hana/detail/operators/logical.hpp>
#include <boost/hana/detail/operators/orderable.hpp>
#include <boost/hana/eval.hpp>
#include <boost/hana/fwd/core/tag_of.hpp>
#include <boost/hana/fwd/eval_if.hpp>
#include <boost/hana/fwd/if.hpp>
#include <boost/hana/fwd/value.hpp>
#include <cstddef>
#include <type_traits>
#include <utility>
BOOST_HANA_NAMESPACE_BEGIN
//////////////////////////////////////////////////////////////////////////
// integral_constant
//////////////////////////////////////////////////////////////////////////
//! @cond
namespace ic_detail {
template <typename T, T N, typename = std::make_integer_sequence<T, N>>
struct go;
template <typename T, T N, T ...i>
struct go<T, N, std::integer_sequence<T, i...>> {
using swallow = T[];
template <typename F>
static constexpr void with_index(F&& f)
{ (void)swallow{T{}, ((void)f(integral_constant<T, i>{}), i)...}; }
template <typename F>
static constexpr void without_index(F&& f)
{ (void)swallow{T{}, ((void)f(), i)...}; }
};
template <typename T, T v>
template <typename F>
constexpr void with_index_t<T, v>::operator()(F&& f) const
{ go<T, ((void)sizeof(&f), v)>::with_index(static_cast<F&&>(f)); }
template <typename T, T v>
template <typename F>
constexpr void times_t<T, v>::operator()(F&& f) const
{ go<T, ((void)sizeof(&f), v)>::without_index(static_cast<F&&>(f)); }
// avoid link-time error
template <typename T, T v>
constexpr with_index_t<T, v> times_t<T, v>::with_index;
}
// avoid link-time error
template <typename T, T v>
constexpr ic_detail::times_t<T, v> integral_constant<T, v>::times;
template <typename T, T v>
struct tag_of<integral_constant<T, v>> {
using type = integral_constant_tag<T>;
};
//! @endcond
//////////////////////////////////////////////////////////////////////////
// Operators
//////////////////////////////////////////////////////////////////////////
namespace detail {
template <typename T>
struct comparable_operators<integral_constant_tag<T>> {
static constexpr bool value = true;
};
template <typename T>
struct orderable_operators<integral_constant_tag<T>> {
static constexpr bool value = true;
};
template <typename T>
struct arithmetic_operators<integral_constant_tag<T>> {
static constexpr bool value = true;
};
template <typename T>
struct logical_operators<integral_constant_tag<T>> {
static constexpr bool value = true;
};
}
#define BOOST_HANA_INTEGRAL_CONSTANT_BINARY_OP(op) \
template <typename U, U u, typename V, V v> \
constexpr integral_constant<decltype(u op v), (u op v)> \
operator op(integral_constant<U, u>, integral_constant<V, v>) \
{ return {}; } \
/**/
#define BOOST_HANA_INTEGRAL_CONSTANT_UNARY_OP(op) \
template <typename U, U u> \
constexpr integral_constant<decltype(op u), (op u)> \
operator op(integral_constant<U, u>) \
{ return {}; } \
/**/
// Arithmetic
BOOST_HANA_INTEGRAL_CONSTANT_UNARY_OP(+)
// Bitwise
BOOST_HANA_INTEGRAL_CONSTANT_UNARY_OP(~)
BOOST_HANA_INTEGRAL_CONSTANT_BINARY_OP(&)
BOOST_HANA_INTEGRAL_CONSTANT_BINARY_OP(|)
BOOST_HANA_INTEGRAL_CONSTANT_BINARY_OP(^)
BOOST_HANA_INTEGRAL_CONSTANT_BINARY_OP(<<)
BOOST_HANA_INTEGRAL_CONSTANT_BINARY_OP(>>)
#undef BOOST_HANA_INTEGRAL_CONSTANT_UNARY_OP
#undef BOOST_HANA_INTEGRAL_CONSTANT_BINARY_OP
//////////////////////////////////////////////////////////////////////////
// User-defined literal
//////////////////////////////////////////////////////////////////////////
namespace ic_detail {
constexpr int to_int(char c) {
int result = 0;
if (c >= 'A' && c <= 'F') {
result = static_cast<int>(c) - static_cast<int>('A') + 10;
}
else if (c >= 'a' && c <= 'f') {
result = static_cast<int>(c) - static_cast<int>('a') + 10;
}
else {
result = static_cast<int>(c) - static_cast<int>('0');
}
return result;
}
template<std::size_t N>
constexpr long long parse(const char (&arr)[N]) {
long long base = 10;
std::size_t offset = 0;
if (N > 2) {
bool starts_with_zero = arr[0] == '0';
bool is_hex = starts_with_zero && arr[1] == 'x';
bool is_binary = starts_with_zero && arr[1] == 'b';
if (is_hex) {
//0xDEADBEEF (hexadecimal)
base = 16;
offset = 2;
}
else if (is_binary) {
//0b101011101 (binary)
base = 2;
offset = 2;
}
else if (starts_with_zero) {
//012345 (octal)
base = 8;
offset = 1;
}
}
long long number = 0;
long long multiplier = 1;
for (std::size_t i = 0; i < N - offset; ++i) {
char c = arr[N - 1 - i];
number += to_int(c) * multiplier;
multiplier *= base;
}
return number;
}
}
namespace literals {
template <char ...c>
constexpr auto operator"" _c() {
return hana::llong<ic_detail::parse<sizeof...(c)>({c...})>{};
}
}
//////////////////////////////////////////////////////////////////////////
// Model of Constant/IntegralConstant
//////////////////////////////////////////////////////////////////////////
template <typename T>
struct IntegralConstant<integral_constant_tag<T>> {
static constexpr bool value = true;
};
template <typename T, typename C>
struct to_impl<integral_constant_tag<T>, C, when<hana::IntegralConstant<C>::value>>
: embedding<is_embedded<typename C::value_type, T>::value>
{
template <typename N>
static constexpr auto apply(N const&)
{ return integral_constant<T, N::value>{}; }
};
//////////////////////////////////////////////////////////////////////////
// Optimizations
//////////////////////////////////////////////////////////////////////////
template <typename T>
struct eval_if_impl<integral_constant_tag<T>> {
template <typename Cond, typename Then, typename Else>
static constexpr decltype(auto)
apply(Cond const&, Then&& t, Else&& e) {
constexpr bool cond = static_cast<bool>(Cond::value);
return eval_if_impl::apply(hana::bool_<cond>{},
static_cast<Then&&>(t),
static_cast<Else&&>(e));
}
template <typename Then, typename Else>
static constexpr decltype(auto)
apply(hana::true_ const&, Then&& t, Else&&)
{ return hana::eval(static_cast<Then&&>(t)); }
template <typename Then, typename Else>
static constexpr decltype(auto)
apply(hana::false_ const&, Then&&, Else&& e)
{ return hana::eval(static_cast<Else&&>(e)); }
};
template <typename T>
struct if_impl<integral_constant_tag<T>> {
template <typename Cond, typename Then, typename Else>
static constexpr decltype(auto)
apply(Cond const&, Then&& t, Else&& e) {
constexpr bool cond = static_cast<bool>(Cond::value);
return if_impl::apply(hana::bool_<cond>{},
static_cast<Then&&>(t),
static_cast<Else&&>(e));
}
//! @todo We could return `Then` instead of `auto` to sometimes save
//! a copy, but that would break some code that would return a
//! reference to a `type` object. I think the code that would be
//! broken should be changed, but more thought needs to be given.
template <typename Then, typename Else>
static constexpr auto
apply(hana::true_ const&, Then&& t, Else&&)
{ return static_cast<Then&&>(t); }
template <typename Then, typename Else>
static constexpr auto
apply(hana::false_ const&, Then&&, Else&& e)
{ return static_cast<Else&&>(e); }
};
BOOST_HANA_NAMESPACE_END
#endif // !BOOST_HANA_BOOL_HPP