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//
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//
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// Copyright (c) 2021 Vinnie Falco (vinnie.falco@gmail.com)
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// Copyright (c) 2021 Vinnie Falco (vinnie.falco@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/cppalliance/http
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// Official repository: https://github.com/cppalliance/http
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//
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//
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#ifndef BOOST_HTTP_RFC_LIST_RULE_HPP
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#ifndef BOOST_HTTP_RFC_LIST_RULE_HPP
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#define BOOST_HTTP_RFC_LIST_RULE_HPP
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#define BOOST_HTTP_RFC_LIST_RULE_HPP
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#include <boost/http/detail/config.hpp>
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#include <boost/http/detail/config.hpp>
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#include <boost/url/grammar/range_rule.hpp>
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#include <boost/url/grammar/range_rule.hpp>
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#include <boost/core/empty_value.hpp>
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#include <boost/core/empty_value.hpp>
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namespace boost {
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namespace boost {
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namespace http {
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namespace http {
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namespace implementation_defined {
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namespace implementation_defined {
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template<class Rule>
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template<class Rule>
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struct list_rule_t
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struct list_rule_t
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    : private empty_value<Rule>
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    : private empty_value<Rule>
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{
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{
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    using value_type = grammar::range<
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    using value_type = grammar::range<
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        typename Rule::value_type>;
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        typename Rule::value_type>;
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    constexpr
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    constexpr
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    list_rule_t(
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    list_rule_t(
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        Rule const& r,
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        Rule const& r,
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        std::size_t n,
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        std::size_t n,
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        std::size_t m) noexcept
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        std::size_t m) noexcept
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        : empty_value<Rule>(
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        : empty_value<Rule>(
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            empty_init, r)
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            empty_init, r)
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        , n_(n)
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        , n_(n)
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        , m_(m)
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        , m_(m)
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    {
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    {
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    }
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    }
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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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private:
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private:
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    struct first_rule;
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    struct first_rule;
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    struct next_rule;
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    struct next_rule;
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    std::size_t n_;
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    std::size_t n_;
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    std::size_t m_;
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    std::size_t m_;
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};
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};
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} // implementation_defined
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} // implementation_defined
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/** Rule for a comma-delimited list of elements
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/** Rule for a comma-delimited list of elements
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    This rule defines a list containing
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    This rule defines a list containing
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    at least n and at most m of Element,
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    at least n and at most m of Element,
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    each separated by at least one comma
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    each separated by at least one comma
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    and optional whitespace.
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    and optional whitespace.
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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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    #element       => [ 1#element ]
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    #element       => [ 1#element ]
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    1#element      => element *( OWS "," OWS element )
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    1#element      => element *( OWS "," OWS element )
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    <n>#<m>element => element <n-1>*<m-1>( OWS "," OWS element )
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    <n>#<m>element => element <n-1>*<m-1>( OWS "," OWS element )
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    @endcode
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    @endcode
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    Senders must emit compliant values, but
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    Senders must emit compliant values, but
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    receivers should accept values generated
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    receivers should accept values generated
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    with the legacy production rules:
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    with the legacy production rules:
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    @par Legacy BNF
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    @par Legacy BNF
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    @code
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    @code
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    #element    => [ ( "," / element ) *( OWS "," [ OWS element ] ) ]
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    #element    => [ ( "," / element ) *( OWS "," [ OWS element ] ) ]
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    1#element   => *( "," OWS ) element *( OWS "," [ OWS element ] )
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    1#element   => *( "," OWS ) element *( OWS "," [ OWS element ] )
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    @endcode
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    @endcode
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    @tparam Rule The rule type.
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    @tparam Rule The rule type.
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    @param r The rule to use for elements.
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    @param r The rule to use for elements.
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    @param n The minimum number of elements, which may be zero.
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    @param n The minimum number of elements, which may be zero.
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    @param m The maximum number of elements.
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    @param m The maximum number of elements.
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    @return A rule that matches the list.
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    @return A rule that matches the list.
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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/rfc7230#section-7"
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    @li <a href="https://datatracker.ietf.org/doc/html/rfc7230#section-7"
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        >5.6.1. Lists (#rule ABNF Extension) (rfc7230)</a>
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        >5.6.1. Lists (#rule ABNF Extension) (rfc7230)</a>
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*/
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*/
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template<class Rule>
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template<class Rule>
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constexpr
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constexpr
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auto
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auto
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list_rule(
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list_rule(
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    Rule const& r,
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    Rule const& r,
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    std::size_t n = 0,
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    std::size_t n = 0,
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    std::size_t m =
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    std::size_t m =
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        std::size_t(-1)) noexcept ->
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        std::size_t(-1)) noexcept ->
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    implementation_defined::list_rule_t<Rule>
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    implementation_defined::list_rule_t<Rule>
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{
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{
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    return implementation_defined::list_rule_t<Rule>(r, n, m);
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    return implementation_defined::list_rule_t<Rule>(r, n, m);
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}
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}
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} // http
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} // http
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} // boost
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} // boost
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#include <boost/http/rfc/impl/list_rule.hpp>
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#include <boost/http/rfc/impl/list_rule.hpp>
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#endif
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#endif