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//
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//
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// Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
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// Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
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//
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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//
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// Official repository: https://github.com/boostorg/url
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// Official repository: https://github.com/boostorg/url
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//
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//
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#ifndef BOOST_URL_GRAMMAR_IMPL_OPTIONAL_RULE_HPP
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#ifndef BOOST_URL_GRAMMAR_IMPL_OPTIONAL_RULE_HPP
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#define BOOST_URL_GRAMMAR_IMPL_OPTIONAL_RULE_HPP
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#define BOOST_URL_GRAMMAR_IMPL_OPTIONAL_RULE_HPP
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#include <boost/url/grammar/error.hpp>
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#include <boost/url/grammar/error.hpp>
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namespace boost {
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namespace boost {
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namespace urls {
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namespace urls {
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namespace grammar {
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namespace grammar {
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template<class R>
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template<class R>
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auto
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auto
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implementation_defined::optional_rule_t<R>::
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implementation_defined::optional_rule_t<R>::
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parse(
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parse(
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    char const*& it,
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    char const*& it,
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    char const* end) const ->
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    char const* end) const ->
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        system::result<value_type>
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        system::result<value_type>
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{
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{
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    if(it == end)
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    if(it == end)
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        return boost::none;
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        return boost::none;
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    auto const it0 = it;
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    auto const it0 = it;
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    auto rv =
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    auto rv =
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        this->get().parse(it, end);
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        this->get().parse(it, end);
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    if(rv)
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    if(rv)
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        return value_type(*rv);
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        return value_type(*rv);
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    it = it0;
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    it = it0;
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    return boost::none;
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    return boost::none;
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}
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}
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} // grammar
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} // grammar
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} // urls
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} // urls
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} // boost
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} // boost
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#endif
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#endif