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//
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//
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// Copyright (c) 2022 Alan de Freitas (alandefreitas@gmail.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_DETAIL_OPTIONAL_STRING_HPP
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#ifndef BOOST_URL_DETAIL_OPTIONAL_STRING_HPP
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#define BOOST_URL_DETAIL_OPTIONAL_STRING_HPP
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#define BOOST_URL_DETAIL_OPTIONAL_STRING_HPP
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#include <boost/url/detail/string_view.hpp>
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#include <boost/url/detail/string_view.hpp>
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#include <boost/core/detail/string_view.hpp>
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#include <boost/core/detail/string_view.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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#ifndef BOOST_URL_DOCS
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#ifndef BOOST_URL_DOCS
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struct no_value_t;
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struct no_value_t;
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#endif
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#endif
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namespace detail {
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namespace detail {
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struct optional_string
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struct optional_string
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{
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{
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    core::string_view s;
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    core::string_view s;
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    bool b = false;
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    bool b = false;
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};
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};
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template <class String>
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template <class String>
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typename std::enable_if<
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typename std::enable_if<
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    std::is_convertible<String, core::string_view>::value,
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    std::is_convertible<String, core::string_view>::value,
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    optional_string>::type
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    optional_string>::type
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get_optional_string(
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get_optional_string(
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    String const& s)
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    String const& s)
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{
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{
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    optional_string r;
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    optional_string r;
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    r.s = s;
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    r.s = s;
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    r.b = true;
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    r.b = true;
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    return r;
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    return r;
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}
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}
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template <class T, class = void>
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template <class T, class = void>
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struct is_dereferenceable : std::false_type
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struct is_dereferenceable : std::false_type
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{};
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{};
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template <class T>
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template <class T>
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struct is_dereferenceable<
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struct is_dereferenceable<
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    T,
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    T,
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    void_t<
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    void_t<
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        decltype(*std::declval<T>())
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        decltype(*std::declval<T>())
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        >> : std::true_type
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        >> : std::true_type
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{};
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{};
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template <class OptionalString>
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template <class OptionalString>
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typename std::enable_if<
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typename std::enable_if<
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    !std::is_convertible<OptionalString, core::string_view>::value,
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    !std::is_convertible<OptionalString, core::string_view>::value,
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    optional_string>::type
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    optional_string>::type
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get_optional_string(
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get_optional_string(
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    OptionalString const& opt)
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    OptionalString const& opt)
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{
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{
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    // If this goes off, it means the rule
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    // If this goes off, it means the rule
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    // passed in did not meet the requirements.
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    // passed in did not meet the requirements.
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    // Please check the documentation of functions
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    // Please check the documentation of functions
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    // that call get_optional_string.
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    // that call get_optional_string.
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    static_assert(
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    static_assert(
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        is_dereferenceable<OptionalString>::value &&
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        is_dereferenceable<OptionalString>::value &&
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        std::is_constructible<bool, OptionalString>::value &&
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        std::is_constructible<bool, OptionalString>::value &&
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        !std::is_convertible<OptionalString, core::string_view>::value &&
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        !std::is_convertible<OptionalString, core::string_view>::value &&
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        std::is_convertible<typename std::decay<decltype(*std::declval<OptionalString>())>::type, core::string_view>::value,
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        std::is_convertible<typename std::decay<decltype(*std::declval<OptionalString>())>::type, core::string_view>::value,
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        "OptionalString requirements not met");
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        "OptionalString requirements not met");
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    optional_string r;
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    optional_string r;
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    r.s = opt ? detail::to_sv(*opt) : core::string_view{};
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    r.s = opt ? detail::to_sv(*opt) : core::string_view{};
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    r.b = static_cast<bool>(opt);
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    r.b = static_cast<bool>(opt);
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    return r;
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    return r;
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}
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}
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inline
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inline
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optional_string
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optional_string
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get_optional_string(
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get_optional_string(
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    std::nullptr_t)
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    std::nullptr_t)
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{
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{
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    return {};
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    return {};
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}
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}
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inline
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inline
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optional_string
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optional_string
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get_optional_string(
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get_optional_string(
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    no_value_t const&)
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    no_value_t const&)
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{
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{
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    return {};
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    return {};
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}
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}
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} // detail
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} // detail
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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