efl/src/lib/eolian_cxx/grammar/integral.hpp

104 lines
3.1 KiB
C++

/*
* Copyright 2019 by its authors. See AUTHORS.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef EOLIAN_CXX_INTEGRAL_HH
#define EOLIAN_CXX_INTEGRAL_HH
#include <cstdlib>
#include <cstring>
#include "grammar/generator.hpp"
#include "grammar/attributes.hpp"
#include "grammar/case.hpp"
namespace efl { namespace eolian { namespace grammar {
namespace detail {
template <typename OutputIterator, typename T>
void generate_integral(OutputIterator sink, T integer)
{
std::stringstream stm;
stm << integer;
std::string string = stm.str();
std::copy(string.begin(), string.end(), sink);
}
}
// literal
template <typename T>
struct literal_integral_generator
{
T integral;
template <typename OutputIterator, typename Attribute, typename Context>
bool generate(OutputIterator sink, Attribute const&, Context const&) const
{
detail::generate_integral(sink, integral);
return true;
}
};
template <typename T, typename Enable = typename std::enable_if<std::is_integral<T>::value>::type>
literal_integral_generator<T> as_generator(T&& literal) { return {std::forward<T>(literal)}; }
literal_integral_generator<std::size_t> as_generator(std::size_t literal) { return {literal}; }
struct integral_terminal {
template <typename T>
literal_integral_generator<T> operator()(T literal) const
{
return {literal};
}
} const int_ = {};
struct integral_generator
{
template <typename OutputIterator, typename Attribute, typename Context>
bool generate(OutputIterator sink, Attribute const& attribute, Context const&) const
{
detail::generate_integral(sink, attribute);
return true;
}
};
integral_generator as_generator(integral_terminal) { return {}; }
template <typename T>
struct is_eager_generator<literal_integral_generator<T>> : std::true_type {};
template <>
struct is_eager_generator<integral_generator> : std::true_type {};
template <typename T>
struct is_generator<literal_integral_generator<T>> : std::true_type {};
template <>
struct is_generator<integral_generator> : std::true_type {};
template <typename T>
struct is_generator<T, typename std::enable_if<std::is_integral<T>::value>::type> : std::true_type {};
template <>
struct is_generator<integral_terminal> : std::true_type {};
namespace type_traits {
template <typename T>
struct attributes_needed<literal_integral_generator<T>> : std::integral_constant<int, 0> {};
template <>
struct attributes_needed<integral_generator> : std::integral_constant<int, 1> {};
template <>
struct attributes_needed<integral_terminal> : std::integral_constant<int, 1> {};
}
} } }
#endif