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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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// Copyright (c) 2022 Alan de Freitas (alandefreitas@gmail.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_VARIANT_RULE_HPP
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#ifndef BOOST_URL_GRAMMAR_VARIANT_RULE_HPP
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#define BOOST_URL_GRAMMAR_VARIANT_RULE_HPP
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#define BOOST_URL_GRAMMAR_VARIANT_RULE_HPP
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#include <boost/url/detail/config.hpp>
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#include <boost/url/detail/config.hpp>
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#include <boost/url/error_types.hpp>
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#include <boost/url/error_types.hpp>
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#include <boost/url/variant.hpp>
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#include <boost/url/variant.hpp>
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#include <boost/url/grammar/detail/tuple.hpp>
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#include <boost/url/grammar/detail/tuple.hpp>
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#include <boost/url/grammar/type_traits.hpp>
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#include <boost/url/grammar/type_traits.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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namespace implementation_defined {
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namespace implementation_defined {
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template<
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template<
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    class R0, class... Rn>
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    class R0, class... Rn>
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class variant_rule_t
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class variant_rule_t
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{
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{
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public:
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public:
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    using value_type = variant2::variant<
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    using value_type = variant2::variant<
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        typename R0::value_type,
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        typename R0::value_type,
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        typename Rn::value_type...>;
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        typename Rn::value_type...>;
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    BOOST_URL_CXX14_CONSTEXPR
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    auto
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    auto
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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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    constexpr
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    constexpr
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    variant_rule_t(
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    variant_rule_t(
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        R0 const& r0,
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        R0 const& r0,
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        Rn const&... rn) noexcept
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        Rn const&... rn) noexcept
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        : rn_(r0, rn...)
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        : rn_(r0, rn...)
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    {
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    {
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    }
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    }
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private:
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private:
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    detail::tuple<R0, Rn...> rn_;
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    detail::tuple<R0, Rn...> rn_;
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};
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};
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} // implementation_defined
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} // implementation_defined
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/** Match one of a set of rules
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/** Match one of a set of rules
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    Each specified rule is tried in sequence.
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    Each specified rule is tried in sequence.
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    When the first match occurs, the result
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    When the first match occurs, the result
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    is stored and returned in the variant. If
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    is stored and returned in the variant. If
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    no match occurs, an error is returned.
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    no match occurs, an error is returned.
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    @param r0 The first rule to match
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    @param r0 The first rule to match
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    @param rn A list of one or more rules to match
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    @param rn A list of one or more rules to match
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    @return The variant rule
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    @return The variant rule
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    @par Value Type
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    @par Value Type
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    @code
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    @code
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    using value_type = variant< typename Rules::value_type... >;
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    using value_type = variant< typename Rules::value_type... >;
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    @endcode
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    @endcode
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    @par Example
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    @par Example
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    Rules are used with the function @ref parse.
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    Rules are used with the function @ref parse.
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    @code
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    @code
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    // request-target = origin-form
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    // request-target = origin-form
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    //                / absolute-form
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    //                / absolute-form
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    //                / authority-form
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    //                / authority-form
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    //                / asterisk-form
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    //                / asterisk-form
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    system::result< variant< url_view, url_view, authority_view, core::string_view > > rv = grammar::parse(
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    system::result< variant< url_view, url_view, authority_view, core::string_view > > rv = grammar::parse(
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        "/index.html?width=full",
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        "/index.html?width=full",
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        variant_rule(
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        variant_rule(
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            origin_form_rule,
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            origin_form_rule,
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            absolute_uri_rule,
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            absolute_uri_rule,
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            authority_rule,
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            authority_rule,
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            delim_rule('*') ) );
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            delim_rule('*') ) );
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    @endcode
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    @endcode
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    @par BNF
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    @par BNF
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    @code
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    @code
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    variant     = rule1 / rule2 / rule3...
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    variant     = rule1 / rule2 / rule3...
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    @endcode
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    @endcode
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    @par Specification
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    @par Specification
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    @li <a href="https://datatracker.ietf.org/doc/html/rfc5234#section-3.2"
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    @li <a href="https://datatracker.ietf.org/doc/html/rfc5234#section-3.2"
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        >3.2.  Alternatives (rfc5234)</a>
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        >3.2.  Alternatives (rfc5234)</a>
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    @li <a href="https://datatracker.ietf.org/doc/html/rfc7230#section-5.3"
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    @li <a href="https://datatracker.ietf.org/doc/html/rfc7230#section-5.3"
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        >5.3.  Request Target (rfc7230)</a>
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        >5.3.  Request Target (rfc7230)</a>
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    @see
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    @see
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        @ref absolute_uri_rule,
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        @ref absolute_uri_rule,
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        @ref authority_rule,
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        @ref authority_rule,
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        @ref delim_rule,
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        @ref delim_rule,
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        @ref parse,
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        @ref parse,
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        @ref origin_form_rule,
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        @ref origin_form_rule,
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        @ref url_view.
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        @ref url_view.
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*/
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*/
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template<
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template<
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    BOOST_URL_CONSTRAINT(Rule) R0,
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    BOOST_URL_CONSTRAINT(Rule) R0,
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    BOOST_URL_CONSTRAINT(Rule)... Rn>
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    BOOST_URL_CONSTRAINT(Rule)... Rn>
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constexpr
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constexpr
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auto
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auto
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variant_rule(
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variant_rule(
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    R0 const& r0,
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    R0 const& r0,
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    Rn const&... rn) noexcept ->
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    Rn const&... rn) noexcept ->
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        implementation_defined::variant_rule_t<R0, Rn...>;
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        implementation_defined::variant_rule_t<R0, Rn...>;
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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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#include <boost/url/grammar/impl/variant_rule.hpp>
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#include <boost/url/grammar/impl/variant_rule.hpp>
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#endif
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#endif