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

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1.8 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_KLEENE_HH
#define EOLIAN_CXX_KLEENE_HH
#include "grammar/generator.hpp"
namespace efl { namespace eolian { namespace grammar {
template <typename Generator>
struct kleene_generator
{
kleene_generator(Generator g)
: generator(g) {}
template <typename OutputIterator, typename Attribute, typename Context>
bool generate(OutputIterator sink, Attribute const& attribute, Context const& context) const
{
bool b;
for(auto&& c : attribute)
{
b = as_generator(generator).generate(sink, c, context);
if(!b)
return false;
}
return true;
}
Generator generator;
};
template <typename Generator>
struct is_eager_generator<kleene_generator<Generator> > : std::true_type {};
template <typename Generator>
struct is_generator<kleene_generator<Generator> > : std::true_type {};
namespace type_traits {
template <typename G>
struct attributes_needed<kleene_generator<G> > : std::integral_constant<int, 1> {};
}
template <typename Generator>
typename std::enable_if<grammar::is_generator<Generator>::value, kleene_generator<Generator>>::type
operator*(Generator g)
{
return kleene_generator<Generator>{g};
}
} } }
#endif