// Copyright 2017-2020 by Martin Moene
//
// string-view lite, a C++17-like string_view for C++98 and later.
// For more information see https://github.com/martinmoene/string-view-lite
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

#pragma once

#ifndef NONSTD_SV_LITE_H_INCLUDED
#    define NONSTD_SV_LITE_H_INCLUDED

#    define string_view_lite_MAJOR 1
#    define string_view_lite_MINOR 4
#    define string_view_lite_PATCH 0

#    define string_view_lite_VERSION                                                               \
        nssv_STRINGIFY(string_view_lite_MAJOR) "." nssv_STRINGIFY(                                 \
            string_view_lite_MINOR) "." nssv_STRINGIFY(string_view_lite_PATCH)

#    define nssv_STRINGIFY(x) nssv_STRINGIFY_(x)
#    define nssv_STRINGIFY_(x) #    x

// string-view lite configuration:

#    define nssv_STRING_VIEW_DEFAULT 0
#    define nssv_STRING_VIEW_NONSTD 1
#    define nssv_STRING_VIEW_STD 2

#    if !defined(nssv_CONFIG_SELECT_STRING_VIEW)
#        define nssv_CONFIG_SELECT_STRING_VIEW                                                     \
            (nssv_HAVE_STD_STRING_VIEW ? nssv_STRING_VIEW_STD : nssv_STRING_VIEW_NONSTD)
#    endif

#    if defined(nssv_CONFIG_SELECT_STD_STRING_VIEW) ||                                             \
        defined(nssv_CONFIG_SELECT_NONSTD_STRING_VIEW)
#        error nssv_CONFIG_SELECT_STD_STRING_VIEW and nssv_CONFIG_SELECT_NONSTD_STRING_VIEW are deprecated and removed, please use nssv_CONFIG_SELECT_STRING_VIEW=nssv_STRING_VIEW_...
#    endif

#    ifndef nssv_CONFIG_STD_SV_OPERATOR
#        define nssv_CONFIG_STD_SV_OPERATOR 0
#    endif

#    ifndef nssv_CONFIG_USR_SV_OPERATOR
#        define nssv_CONFIG_USR_SV_OPERATOR 1
#    endif

#    ifdef nssv_CONFIG_CONVERSION_STD_STRING
#        define nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS nssv_CONFIG_CONVERSION_STD_STRING
#        define nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS nssv_CONFIG_CONVERSION_STD_STRING
#    endif

#    ifndef nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS
#        define nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS 1
#    endif

#    ifndef nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
#        define nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS 1
#    endif

// Control presence of exception handling (try and auto discover):

#    ifndef nssv_CONFIG_NO_EXCEPTIONS
#        if defined(__cpp_exceptions) || defined(__EXCEPTIONS) || defined(_CPPUNWIND)
#            define nssv_CONFIG_NO_EXCEPTIONS 0
#        else
#            define nssv_CONFIG_NO_EXCEPTIONS 1
#        endif
#    endif

// C++ language version detection (C++20 is speculative):
// Note: VC14.0/1900 (VS2015) lacks too much from C++14.

#    ifndef nssv_CPLUSPLUS
#        if defined(_MSVC_LANG) && !defined(__clang__)
#            define nssv_CPLUSPLUS (_MSC_VER == 1900 ? 201103L : _MSVC_LANG)
#        else
#            define nssv_CPLUSPLUS __cplusplus
#        endif
#    endif

#    define nssv_CPP98_OR_GREATER (nssv_CPLUSPLUS >= 199711L)
#    define nssv_CPP11_OR_GREATER (nssv_CPLUSPLUS >= 201103L)
#    define nssv_CPP11_OR_GREATER_ (nssv_CPLUSPLUS >= 201103L)
#    define nssv_CPP14_OR_GREATER (nssv_CPLUSPLUS >= 201402L)
#    define nssv_CPP17_OR_GREATER (nssv_CPLUSPLUS >= 201703L)
#    define nssv_CPP20_OR_GREATER (nssv_CPLUSPLUS >= 202000L)

// use C++17 std::string_view if available and requested:

#    if nssv_CPP17_OR_GREATER && defined(__has_include)
#        if __has_include(<string_view> )
#            define nssv_HAVE_STD_STRING_VIEW 1
#        else
#            define nssv_HAVE_STD_STRING_VIEW 0
#        endif
#    else
#        define nssv_HAVE_STD_STRING_VIEW 0
#    endif

#    define nssv_USES_STD_STRING_VIEW                                                              \
        ((nssv_CONFIG_SELECT_STRING_VIEW == nssv_STRING_VIEW_STD) ||                               \
         ((nssv_CONFIG_SELECT_STRING_VIEW == nssv_STRING_VIEW_DEFAULT) &&                          \
          nssv_HAVE_STD_STRING_VIEW))

#    define nssv_HAVE_STARTS_WITH (nssv_CPP20_OR_GREATER || !nssv_USES_STD_STRING_VIEW)
#    define nssv_HAVE_ENDS_WITH nssv_HAVE_STARTS_WITH

//
// Use C++17 std::string_view:
//

#    if nssv_USES_STD_STRING_VIEW

#        include <string_view>

// Extensions for std::string:

#        if nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS

namespace rapidfuzz {

template <class CharT, class Traits, class Allocator = std::allocator<CharT>>
std::basic_string<CharT, Traits, Allocator> to_string(std::basic_string_view<CharT, Traits> v,
                                                      Allocator const& a = Allocator())
{
    return std::basic_string<CharT, Traits, Allocator>(v.begin(), v.end(), a);
}

template <class CharT, class Traits, class Allocator>
std::basic_string_view<CharT, Traits>
to_string_view(std::basic_string<CharT, Traits, Allocator> const& s)
{
    return std::basic_string_view<CharT, Traits>(s.data(), s.size());
}

// Literal operators sv and _sv:

#            if nssv_CONFIG_STD_SV_OPERATOR

using namespace std::literals::string_view_literals;

#            endif

#            if nssv_CONFIG_USR_SV_OPERATOR

inline namespace literals {
inline namespace string_view_literals {

constexpr std::string_view operator"" _sv(const char* str, size_t len) noexcept // (1)
{
    return std::string_view{str, len};
}

constexpr std::u16string_view operator"" _sv(const char16_t* str, size_t len) noexcept // (2)
{
    return std::u16string_view{str, len};
}

constexpr std::u32string_view operator"" _sv(const char32_t* str, size_t len) noexcept // (3)
{
    return std::u32string_view{str, len};
}

constexpr std::wstring_view operator"" _sv(const wchar_t* str, size_t len) noexcept // (4)
{
    return std::wstring_view{str, len};
}

} // namespace string_view_literals
} // namespace literals

#            endif // nssv_CONFIG_USR_SV_OPERATOR

} // namespace rapidfuzz

#        endif // nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS

namespace rapidfuzz {

using std::basic_string_view;
using std::string_view;
using std::u16string_view;
using std::u32string_view;
using std::wstring_view;

// literal "sv" and "_sv", see above

using std::operator==;
using std::operator!=;
using std::operator<;
using std::operator<=;
using std::operator>;
using std::operator>=;

using std::operator<<;

} // namespace rapidfuzz

#    else // nssv_HAVE_STD_STRING_VIEW

//
// Before C++17: use string_view lite:
//

// Compiler versions:
//
// MSVC++  6.0  _MSC_VER == 1200  nssv_COMPILER_MSVC_VERSION ==  60  (Visual Studio 6.0)
// MSVC++  7.0  _MSC_VER == 1300  nssv_COMPILER_MSVC_VERSION ==  70  (Visual Studio .NET 2002)
// MSVC++  7.1  _MSC_VER == 1310  nssv_COMPILER_MSVC_VERSION ==  71  (Visual Studio .NET 2003)
// MSVC++  8.0  _MSC_VER == 1400  nssv_COMPILER_MSVC_VERSION ==  80  (Visual Studio 2005)
// MSVC++  9.0  _MSC_VER == 1500  nssv_COMPILER_MSVC_VERSION ==  90  (Visual Studio 2008)
// MSVC++ 10.0  _MSC_VER == 1600  nssv_COMPILER_MSVC_VERSION == 100  (Visual Studio 2010)
// MSVC++ 11.0  _MSC_VER == 1700  nssv_COMPILER_MSVC_VERSION == 110  (Visual Studio 2012)
// MSVC++ 12.0  _MSC_VER == 1800  nssv_COMPILER_MSVC_VERSION == 120  (Visual Studio 2013)
// MSVC++ 14.0  _MSC_VER == 1900  nssv_COMPILER_MSVC_VERSION == 140  (Visual Studio 2015)
// MSVC++ 14.1  _MSC_VER >= 1910  nssv_COMPILER_MSVC_VERSION == 141  (Visual Studio 2017)
// MSVC++ 14.2  _MSC_VER >= 1920  nssv_COMPILER_MSVC_VERSION == 142  (Visual Studio 2019)

#        if defined(_MSC_VER) && !defined(__clang__)
#            define nssv_COMPILER_MSVC_VER (_MSC_VER)
#            define nssv_COMPILER_MSVC_VERSION (_MSC_VER / 10 - 10 * (5 + (_MSC_VER < 1900)))
#        else
#            define nssv_COMPILER_MSVC_VER 0
#            define nssv_COMPILER_MSVC_VERSION 0
#        endif

#        define nssv_COMPILER_VERSION(major, minor, patch) (10 * (10 * (major) + (minor)) + (patch))

#        if defined(__clang__)
#            define nssv_COMPILER_CLANG_VERSION                                                    \
                nssv_COMPILER_VERSION(__clang_major__, __clang_minor__, __clang_patchlevel__)
#        else
#            define nssv_COMPILER_CLANG_VERSION 0
#        endif

#        if defined(__GNUC__) && !defined(__clang__)
#            define nssv_COMPILER_GNUC_VERSION                                                     \
                nssv_COMPILER_VERSION(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__)
#        else
#            define nssv_COMPILER_GNUC_VERSION 0
#        endif

// half-open range [lo..hi):
#        define nssv_BETWEEN(v, lo, hi) ((lo) <= (v) && (v) < (hi))

// Presence of language and library features:

#        ifdef _HAS_CPP0X
#            define nssv_HAS_CPP0X _HAS_CPP0X
#        else
#            define nssv_HAS_CPP0X 0
#        endif

// Unless defined otherwise below, consider VC14 as C++11 for variant-lite:

#        if nssv_COMPILER_MSVC_VER >= 1900
#            undef nssv_CPP11_OR_GREATER
#            define nssv_CPP11_OR_GREATER 1
#        endif

#        define nssv_CPP11_90 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1500)
#        define nssv_CPP11_100 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1600)
#        define nssv_CPP11_110 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1700)
#        define nssv_CPP11_120 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1800)
#        define nssv_CPP11_140 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1900)
#        define nssv_CPP11_141 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1910)

#        define nssv_CPP14_000 (nssv_CPP14_OR_GREATER)
#        define nssv_CPP17_000 (nssv_CPP17_OR_GREATER)

// Presence of C++11 language features:

#        define nssv_HAVE_CONSTEXPR_11 nssv_CPP11_140
#        define nssv_HAVE_EXPLICIT_CONVERSION nssv_CPP11_140
#        define nssv_HAVE_INLINE_NAMESPACE nssv_CPP11_140
#        define nssv_HAVE_NOEXCEPT nssv_CPP11_140
#        define nssv_HAVE_NULLPTR nssv_CPP11_100
#        define nssv_HAVE_REF_QUALIFIER nssv_CPP11_140
#        define nssv_HAVE_UNICODE_LITERALS nssv_CPP11_140
#        define nssv_HAVE_USER_DEFINED_LITERALS nssv_CPP11_140
#        define nssv_HAVE_WCHAR16_T nssv_CPP11_100
#        define nssv_HAVE_WCHAR32_T nssv_CPP11_100

#        if !((nssv_CPP11_OR_GREATER && nssv_COMPILER_CLANG_VERSION) ||                            \
              nssv_BETWEEN(nssv_COMPILER_CLANG_VERSION, 300, 400))
#            define nssv_HAVE_STD_DEFINED_LITERALS nssv_CPP11_140
#        else
#            define nssv_HAVE_STD_DEFINED_LITERALS 0
#        endif

// Presence of C++14 language features:

#        define nssv_HAVE_CONSTEXPR_14 nssv_CPP14_000

// Presence of C++17 language features:

#        define nssv_HAVE_NODISCARD nssv_CPP17_000

// Presence of C++ library features:

#        define nssv_HAVE_STD_HASH nssv_CPP11_120

// C++ feature usage:

#        if nssv_HAVE_CONSTEXPR_11
#            define nssv_constexpr constexpr
#        else
#            define nssv_constexpr /*constexpr*/
#        endif

#        if nssv_HAVE_CONSTEXPR_14
#            define nssv_constexpr14 constexpr
#        else
#            define nssv_constexpr14 /*constexpr*/
#        endif

#        if nssv_HAVE_EXPLICIT_CONVERSION
#            define nssv_explicit explicit
#        else
#            define nssv_explicit /*explicit*/
#        endif

#        if nssv_HAVE_INLINE_NAMESPACE
#            define nssv_inline_ns inline
#        else
#            define nssv_inline_ns /*inline*/
#        endif

#        if nssv_HAVE_NOEXCEPT
#            define nssv_noexcept noexcept
#        else
#            define nssv_noexcept /*noexcept*/
#        endif

//#if nssv_HAVE_REF_QUALIFIER
//# define nssv_ref_qual  &
//# define nssv_refref_qual  &&
//#else
//# define nssv_ref_qual  /*&*/
//# define nssv_refref_qual  /*&&*/
//#endif

#        if nssv_HAVE_NULLPTR
#            define nssv_nullptr nullptr
#        else
#            define nssv_nullptr NULL
#        endif

#        if nssv_HAVE_NODISCARD
#            define nssv_nodiscard [[nodiscard]]
#        else
#            define nssv_nodiscard /*[[nodiscard]]*/
#        endif

// Additional includes:

#        include <algorithm>
#        include <cassert>
#        include <iterator>
#        include <limits>
#        include <ostream>
#        include <string> // std::char_traits<>

#        if !nssv_CONFIG_NO_EXCEPTIONS
#            include <stdexcept>
#        endif

#        if nssv_CPP11_OR_GREATER
#            include <type_traits>
#        endif

// Clang, GNUC, MSVC warning suppression macros:

#        if defined(__clang__)
#            pragma clang diagnostic ignored "-Wreserved-user-defined-literal"
#            pragma clang diagnostic push
#            pragma clang diagnostic ignored "-Wuser-defined-literals"
#        elif defined(__GNUC__)
#            pragma GCC diagnostic push
#            pragma GCC diagnostic ignored "-Wliteral-suffix"
#        endif // __clang__

#        if nssv_COMPILER_MSVC_VERSION >= 140
#            define nssv_SUPPRESS_MSGSL_WARNING(expr) [[gsl::suppress(expr)]]
#            define nssv_SUPPRESS_MSVC_WARNING(code, descr) __pragma(warning(suppress : code))
#            define nssv_DISABLE_MSVC_WARNINGS(codes)                                              \
                __pragma(warning(push)) __pragma(warning(disable : codes))
#        else
#            define nssv_SUPPRESS_MSGSL_WARNING(expr)
#            define nssv_SUPPRESS_MSVC_WARNING(code, descr)
#            define nssv_DISABLE_MSVC_WARNINGS(codes)
#        endif

#        if defined(__clang__)
#            define nssv_RESTORE_WARNINGS() _Pragma("clang diagnostic pop")
#        elif defined(__GNUC__)
#            define nssv_RESTORE_WARNINGS() _Pragma("GCC diagnostic pop")
#        elif nssv_COMPILER_MSVC_VERSION >= 140
#            define nssv_RESTORE_WARNINGS() __pragma(warning(pop))
#        else
#            define nssv_RESTORE_WARNINGS()
#        endif

// Suppress the following MSVC (GSL) warnings:
// - C4455, non-gsl   : 'operator ""sv': literal suffix identifiers that do not
//                      start with an underscore are reserved
// - C26472, gsl::t.1 : don't use a static_cast for arithmetic conversions;
//                      use brace initialization, gsl::narrow_cast or gsl::narow
// - C26481: gsl::b.1 : don't use pointer arithmetic. Use span instead

nssv_DISABLE_MSVC_WARNINGS(4455 26481 26472)
    // nssv_DISABLE_CLANG_WARNINGS( "-Wuser-defined-literals" )
    // nssv_DISABLE_GNUC_WARNINGS( -Wliteral-suffix )

    namespace rapidfuzz
{
    namespace sv_lite {

#        if nssv_CPP11_OR_GREATER

    namespace detail {

#            if nssv_CPP14_OR_GREATER

    template <typename CharT>
    inline constexpr std::size_t length(CharT* s, std::size_t result = 0)
    {
        CharT* v = s;
        std::size_t r = result;
        while (*v != '\0') {
            ++v;
            ++r;
        }
        return r;
    }

#            else // nssv_CPP14_OR_GREATER

    // Expect tail call optimization to make length() non-recursive:

    template <typename CharT>
    inline constexpr std::size_t length(CharT* s, std::size_t result = 0)
    {
        return *s == '\0' ? result : length(s + 1, result + 1);
    }

#            endif // nssv_CPP14_OR_GREATER

    } // namespace detail

#        endif // nssv_CPP11_OR_GREATER

    template <class CharT, class Traits = std::char_traits<CharT>>
    class basic_string_view;

    //
    // basic_string_view:
    //

    template <class CharT, class Traits /* = std::char_traits<CharT> */
              >
    class basic_string_view {
    public:
        // Member types:

        typedef Traits traits_type;
        typedef CharT value_type;

        typedef CharT* pointer;
        typedef CharT const* const_pointer;
        typedef CharT& reference;
        typedef CharT const& const_reference;

        typedef const_pointer iterator;
        typedef const_pointer const_iterator;
        typedef std::reverse_iterator<const_iterator> reverse_iterator;
        typedef std::reverse_iterator<const_iterator> const_reverse_iterator;

        typedef std::size_t size_type;
        typedef std::ptrdiff_t difference_type;

        // 24.4.2.1 Construction and assignment:

        nssv_constexpr basic_string_view() nssv_noexcept : data_(nssv_nullptr), size_(0)
        {}

#        if nssv_CPP11_OR_GREATER
        nssv_constexpr basic_string_view(basic_string_view const& other) nssv_noexcept = default;
#        else
        nssv_constexpr basic_string_view(basic_string_view const& other) nssv_noexcept
            : data_(other.data_),
              size_(other.size_)
        {}
#        endif

        nssv_constexpr basic_string_view(CharT const* s,
                                         size_type count) nssv_noexcept // non-standard noexcept
            : data_(s),
              size_(count)
        {}

        nssv_constexpr basic_string_view(CharT const* s) nssv_noexcept // non-standard noexcept
            : data_(s)
#        if nssv_CPP17_OR_GREATER
            ,
              size_(Traits::length(s))
#        elif nssv_CPP11_OR_GREATER
            ,
              size_(detail::length(s))
#        else
            ,
              size_(Traits::length(s))
#        endif
        {}

        // Assignment:

#        if nssv_CPP11_OR_GREATER
        nssv_constexpr14 basic_string_view&
        operator=(basic_string_view const& other) nssv_noexcept = default;
#        else
        nssv_constexpr14 basic_string_view& operator=(basic_string_view const& other) nssv_noexcept
        {
            data_ = other.data_;
            size_ = other.size_;
            return *this;
        }
#        endif

        // 24.4.2.2 Iterator support:

        nssv_constexpr const_iterator begin() const nssv_noexcept
        {
            return data_;
        }
        nssv_constexpr const_iterator end() const nssv_noexcept
        {
            return data_ + size_;
        }

        nssv_constexpr const_iterator cbegin() const nssv_noexcept
        {
            return begin();
        }
        nssv_constexpr const_iterator cend() const nssv_noexcept
        {
            return end();
        }

        nssv_constexpr const_reverse_iterator rbegin() const nssv_noexcept
        {
            return const_reverse_iterator(end());
        }
        nssv_constexpr const_reverse_iterator rend() const nssv_noexcept
        {
            return const_reverse_iterator(begin());
        }

        nssv_constexpr const_reverse_iterator crbegin() const nssv_noexcept
        {
            return rbegin();
        }
        nssv_constexpr const_reverse_iterator crend() const nssv_noexcept
        {
            return rend();
        }

        // 24.4.2.3 Capacity:

        nssv_constexpr size_type size() const nssv_noexcept
        {
            return size_;
        }
        nssv_constexpr size_type length() const nssv_noexcept
        {
            return size_;
        }
        nssv_constexpr size_type max_size() const nssv_noexcept
        {
            return (std::numeric_limits<size_type>::max)();
        }

        // since C++20
        nssv_nodiscard nssv_constexpr bool empty() const nssv_noexcept
        {
            return 0 == size_;
        }

        // 24.4.2.4 Element access:

        nssv_constexpr const_reference operator[](size_type pos) const
        {
            return data_at(pos);
        }

        nssv_constexpr14 const_reference at(size_type pos) const
        {
#        if nssv_CONFIG_NO_EXCEPTIONS
            assert(pos < size());
#        else
            if (pos >= size()) {
                throw std::out_of_range("rapidfuzz::string_view::at()");
            }
#        endif
            return data_at(pos);
        }

        nssv_constexpr const_reference front() const
        {
            return data_at(0);
        }
        nssv_constexpr const_reference back() const
        {
            return data_at(size() - 1);
        }

        nssv_constexpr const_pointer data() const nssv_noexcept
        {
            return data_;
        }

        // 24.4.2.5 Modifiers:

        nssv_constexpr14 void remove_prefix(size_type n)
        {
            assert(n <= size());
            data_ += n;
            size_ -= n;
        }

        nssv_constexpr14 void remove_suffix(size_type n)
        {
            assert(n <= size());
            size_ -= n;
        }

        nssv_constexpr14 void swap(basic_string_view& other) nssv_noexcept
        {
            using std::swap;
            swap(data_, other.data_);
            swap(size_, other.size_);
        }

        // 24.4.2.6 String operations:

        size_type copy(CharT* dest, size_type n, size_type pos = 0) const
        {
#        if nssv_CONFIG_NO_EXCEPTIONS
            assert(pos <= size());
#        else
            if (pos > size()) {
                throw std::out_of_range("rapidfuzz::string_view::copy()");
            }
#        endif
            const size_type rlen = (std::min)(n, size() - pos);

            (void)Traits::copy(dest, data() + pos, rlen);

            return rlen;
        }

        nssv_constexpr14 basic_string_view substr(size_type pos = 0, size_type n = npos) const
        {
#        if nssv_CONFIG_NO_EXCEPTIONS
            assert(pos <= size());
#        else
            if (pos > size()) {
                throw std::out_of_range("rapidfuzz::string_view::substr()");
            }
#        endif
            return basic_string_view(data() + pos, (std::min)(n, size() - pos));
        }

        // compare(), 6x:

        nssv_constexpr14 int compare(basic_string_view other) const nssv_noexcept // (1)
        {
            if (const int result =
                    Traits::compare(data(), other.data(), (std::min)(size(), other.size()))) {
                return result;
            }

            return size() == other.size() ? 0 : size() < other.size() ? -1 : 1;
        }

        nssv_constexpr int compare(size_type pos1, size_type n1,
                                   basic_string_view other) const // (2)
        {
            return substr(pos1, n1).compare(other);
        }

        nssv_constexpr int compare(size_type pos1, size_type n1, basic_string_view other,
                                   size_type pos2, size_type n2) const // (3)
        {
            return substr(pos1, n1).compare(other.substr(pos2, n2));
        }

        nssv_constexpr int compare(CharT const* s) const // (4)
        {
            return compare(basic_string_view(s));
        }

        nssv_constexpr int compare(size_type pos1, size_type n1, CharT const* s) const // (5)
        {
            return substr(pos1, n1).compare(basic_string_view(s));
        }

        nssv_constexpr int compare(size_type pos1, size_type n1, CharT const* s,
                                   size_type n2) const // (6)
        {
            return substr(pos1, n1).compare(basic_string_view(s, n2));
        }

        // 24.4.2.7 Searching:

        // starts_with(), 3x, since C++20:

        nssv_constexpr bool starts_with(basic_string_view v) const nssv_noexcept // (1)
        {
            return size() >= v.size() && compare(0, v.size(), v) == 0;
        }

        nssv_constexpr bool starts_with(CharT c) const nssv_noexcept // (2)
        {
            return starts_with(basic_string_view(&c, 1));
        }

        nssv_constexpr bool starts_with(CharT const* s) const // (3)
        {
            return starts_with(basic_string_view(s));
        }

        // ends_with(), 3x, since C++20:

        nssv_constexpr bool ends_with(basic_string_view v) const nssv_noexcept // (1)
        {
            return size() >= v.size() && compare(size() - v.size(), npos, v) == 0;
        }

        nssv_constexpr bool ends_with(CharT c) const nssv_noexcept // (2)
        {
            return ends_with(basic_string_view(&c, 1));
        }

        nssv_constexpr bool ends_with(CharT const* s) const // (3)
        {
            return ends_with(basic_string_view(s));
        }

        // find(), 4x:

        nssv_constexpr14 size_type find(basic_string_view v,
                                        size_type pos = 0) const nssv_noexcept // (1)
        {
            return assert(v.size() == 0 || v.data() != nssv_nullptr),
                   pos >= size() ? npos
                                 : to_pos(std::search(cbegin() + pos, cend(), v.cbegin(), v.cend(),
                                                      Traits::eq));
        }

        nssv_constexpr14 size_type find(CharT c, size_type pos = 0) const nssv_noexcept // (2)
        {
            return find(basic_string_view(&c, 1), pos);
        }

        nssv_constexpr14 size_type find(CharT const* s, size_type pos, size_type n) const // (3)
        {
            return find(basic_string_view(s, n), pos);
        }

        nssv_constexpr14 size_type find(CharT const* s, size_type pos = 0) const // (4)
        {
            return find(basic_string_view(s), pos);
        }

        // rfind(), 4x:

        nssv_constexpr14 size_type rfind(basic_string_view v,
                                         size_type pos = npos) const nssv_noexcept // (1)
        {
            if (size() < v.size()) {
                return npos;
            }

            if (v.empty()) {
                return (std::min)(size(), pos);
            }

            const_iterator last = cbegin() + (std::min)(size() - v.size(), pos) + v.size();
            const_iterator result = std::find_end(cbegin(), last, v.cbegin(), v.cend(), Traits::eq);

            return result != last ? size_type(result - cbegin()) : npos;
        }

        nssv_constexpr14 size_type rfind(CharT c, size_type pos = npos) const nssv_noexcept // (2)
        {
            return rfind(basic_string_view(&c, 1), pos);
        }

        nssv_constexpr14 size_type rfind(CharT const* s, size_type pos, size_type n) const // (3)
        {
            return rfind(basic_string_view(s, n), pos);
        }

        nssv_constexpr14 size_type rfind(CharT const* s, size_type pos = npos) const // (4)
        {
            return rfind(basic_string_view(s), pos);
        }

        // find_first_of(), 4x:

        nssv_constexpr size_type find_first_of(basic_string_view v,
                                               size_type pos = 0) const nssv_noexcept // (1)
        {
            return pos >= size() ? npos
                                 : to_pos(std::find_first_of(cbegin() + pos, cend(), v.cbegin(),
                                                             v.cend(), Traits::eq));
        }

        nssv_constexpr size_type find_first_of(CharT c,
                                               size_type pos = 0) const nssv_noexcept // (2)
        {
            return find_first_of(basic_string_view(&c, 1), pos);
        }

        nssv_constexpr size_type find_first_of(CharT const* s, size_type pos,
                                               size_type n) const // (3)
        {
            return find_first_of(basic_string_view(s, n), pos);
        }

        nssv_constexpr size_type find_first_of(CharT const* s, size_type pos = 0) const // (4)
        {
            return find_first_of(basic_string_view(s), pos);
        }

        // find_last_of(), 4x:

        nssv_constexpr size_type find_last_of(basic_string_view v,
                                              size_type pos = npos) const nssv_noexcept // (1)
        {
            return empty() ? npos
                   : pos >= size()
                       ? find_last_of(v, size() - 1)
                       : to_pos(std::find_first_of(const_reverse_iterator(cbegin() + pos + 1),
                                                   crend(), v.cbegin(), v.cend(), Traits::eq));
        }

        nssv_constexpr size_type find_last_of(CharT c,
                                              size_type pos = npos) const nssv_noexcept // (2)
        {
            return find_last_of(basic_string_view(&c, 1), pos);
        }

        nssv_constexpr size_type find_last_of(CharT const* s, size_type pos,
                                              size_type count) const // (3)
        {
            return find_last_of(basic_string_view(s, count), pos);
        }

        nssv_constexpr size_type find_last_of(CharT const* s, size_type pos = npos) const // (4)
        {
            return find_last_of(basic_string_view(s), pos);
        }

        // find_first_not_of(), 4x:

        nssv_constexpr size_type find_first_not_of(basic_string_view v,
                                                   size_type pos = 0) const nssv_noexcept // (1)
        {
            return pos >= size() ? npos
                                 : to_pos(std::find_if(cbegin() + pos, cend(), not_in_view(v)));
        }

        nssv_constexpr size_type find_first_not_of(CharT c,
                                                   size_type pos = 0) const nssv_noexcept // (2)
        {
            return find_first_not_of(basic_string_view(&c, 1), pos);
        }

        nssv_constexpr size_type find_first_not_of(CharT const* s, size_type pos,
                                                   size_type count) const // (3)
        {
            return find_first_not_of(basic_string_view(s, count), pos);
        }

        nssv_constexpr size_type find_first_not_of(CharT const* s, size_type pos = 0) const // (4)
        {
            return find_first_not_of(basic_string_view(s), pos);
        }

        // find_last_not_of(), 4x:

        nssv_constexpr size_type find_last_not_of(basic_string_view v,
                                                  size_type pos = npos) const nssv_noexcept // (1)
        {
            return empty()         ? npos
                   : pos >= size() ? find_last_not_of(v, size() - 1)
                                   : to_pos(std::find_if(const_reverse_iterator(cbegin() + pos + 1),
                                                         crend(), not_in_view(v)));
        }

        nssv_constexpr size_type find_last_not_of(CharT c,
                                                  size_type pos = npos) const nssv_noexcept // (2)
        {
            return find_last_not_of(basic_string_view(&c, 1), pos);
        }

        nssv_constexpr size_type find_last_not_of(CharT const* s, size_type pos,
                                                  size_type count) const // (3)
        {
            return find_last_not_of(basic_string_view(s, count), pos);
        }

        nssv_constexpr size_type find_last_not_of(CharT const* s, size_type pos = npos) const // (4)
        {
            return find_last_not_of(basic_string_view(s), pos);
        }

        // Constants:

#        if nssv_CPP17_OR_GREATER
        static nssv_constexpr size_type npos = size_type(-1);
#        elif nssv_CPP11_OR_GREATER
        enum : size_type { npos = size_type(-1) };
#        else
        enum { npos = size_type(-1) };
#        endif

    private:
        struct not_in_view {
            const basic_string_view v;

            nssv_constexpr explicit not_in_view(basic_string_view v_) : v(v_)
            {}

            nssv_constexpr bool operator()(CharT c) const
            {
                return npos == v.find_first_of(c);
            }
        };

        nssv_constexpr size_type to_pos(const_iterator it) const
        {
            return it == cend() ? npos : size_type(it - cbegin());
        }

        nssv_constexpr size_type to_pos(const_reverse_iterator it) const
        {
            return it == crend() ? npos : size_type(crend() - it - 1);
        }

        nssv_constexpr const_reference data_at(size_type pos) const
        {
#        if nssv_BETWEEN(nssv_COMPILER_GNUC_VERSION, 1, 500)
            return data_[pos];
#        else
            return assert(pos < size()), data_[pos];
#        endif
        }

    private:
        const_pointer data_;
        size_type size_;

    public:
#        if nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS

        template <class Allocator>
        basic_string_view(std::basic_string<CharT, Traits, Allocator> const& s) nssv_noexcept
            : data_(s.data()),
              size_(s.size())
        {}

#            if nssv_HAVE_EXPLICIT_CONVERSION

        template <class Allocator>
        explicit operator std::basic_string<CharT, Traits, Allocator>() const
        {
            return to_string(Allocator());
        }

#            endif // nssv_HAVE_EXPLICIT_CONVERSION

#            if nssv_CPP11_OR_GREATER

        template <class Allocator = std::allocator<CharT>>
        std::basic_string<CharT, Traits, Allocator>
        to_string(Allocator const& a = Allocator()) const
        {
            return std::basic_string<CharT, Traits, Allocator>(begin(), end(), a);
        }

#            else

        std::basic_string<CharT, Traits> to_string() const
        {
            return std::basic_string<CharT, Traits>(begin(), end());
        }

        template <class Allocator>
        std::basic_string<CharT, Traits, Allocator> to_string(Allocator const& a) const
        {
            return std::basic_string<CharT, Traits, Allocator>(begin(), end(), a);
        }

#            endif // nssv_CPP11_OR_GREATER

#        endif // nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS
    };

    //
    // Non-member functions:
    //

    // 24.4.3 Non-member comparison functions:
    // lexicographically compare two string views (function template):

    template <class CharT, class Traits>
    nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) == 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) != 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
                                  basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) < 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) <= 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
                                  basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) > 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) >= 0;
    }

    // Let S be basic_string_view<CharT, Traits>, and sv be an instance of S.
    // Implementations shall provide sufficient additional overloads marked
    // constexpr and noexcept so that an object t with an implicit conversion
    // to S can be compared according to Table 67.

#        if !nssv_CPP11_OR_GREATER || nssv_BETWEEN(nssv_COMPILER_MSVC_VERSION, 100, 141)

    // accomodate for older compilers:

    // ==

    template <class CharT, class Traits>
    nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
                                   CharT const* rhs) nssv_noexcept
    {
        return lhs.compare(rhs) == 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator==(CharT const* lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return rhs.compare(lhs) == 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
                                   std::basic_string<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.size() == rhs.size() && lhs.compare(rhs) == 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator==(std::basic_string<CharT, Traits> rhs,
                                   basic_string_view<CharT, Traits> lhs) nssv_noexcept
    {
        return lhs.size() == rhs.size() && lhs.compare(rhs) == 0;
    }

    // !=

    template <class CharT, class Traits>
    nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
                                   char const* rhs) nssv_noexcept
    {
        return lhs.compare(rhs) != 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator!=(char const* lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return rhs.compare(lhs) != 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
                                   std::basic_string<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.size() != rhs.size() && lhs.compare(rhs) != 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator!=(std::basic_string<CharT, Traits> rhs,
                                   basic_string_view<CharT, Traits> lhs) nssv_noexcept
    {
        return lhs.size() != rhs.size() || rhs.compare(lhs) != 0;
    }

    // <

    template <class CharT, class Traits>
    nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
                                  char const* rhs) nssv_noexcept
    {
        return lhs.compare(rhs) < 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator<(char const* lhs,
                                  basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return rhs.compare(lhs) > 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
                                  std::basic_string<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) < 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator<(std::basic_string<CharT, Traits> rhs,
                                  basic_string_view<CharT, Traits> lhs) nssv_noexcept
    {
        return rhs.compare(lhs) > 0;
    }

    // <=

    template <class CharT, class Traits>
    nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
                                   char const* rhs) nssv_noexcept
    {
        return lhs.compare(rhs) <= 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator<=(char const* lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return rhs.compare(lhs) >= 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
                                   std::basic_string<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) <= 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator<=(std::basic_string<CharT, Traits> rhs,
                                   basic_string_view<CharT, Traits> lhs) nssv_noexcept
    {
        return rhs.compare(lhs) >= 0;
    }

    // >

    template <class CharT, class Traits>
    nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
                                  char const* rhs) nssv_noexcept
    {
        return lhs.compare(rhs) > 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator>(char const* lhs,
                                  basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return rhs.compare(lhs) < 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
                                  std::basic_string<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) > 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator>(std::basic_string<CharT, Traits> rhs,
                                  basic_string_view<CharT, Traits> lhs) nssv_noexcept
    {
        return rhs.compare(lhs) < 0;
    }

    // >=

    template <class CharT, class Traits>
    nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
                                   char const* rhs) nssv_noexcept
    {
        return lhs.compare(rhs) >= 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator>=(char const* lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return rhs.compare(lhs) <= 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
                                   std::basic_string<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) >= 0;
    }

    template <class CharT, class Traits>
    nssv_constexpr bool operator>=(std::basic_string<CharT, Traits> rhs,
                                   basic_string_view<CharT, Traits> lhs) nssv_noexcept
    {
        return rhs.compare(lhs) <= 0;
    }

#        else // newer compilers:

#            define nssv_BASIC_STRING_VIEW_I(T, U)                                                 \
                typename std::decay<basic_string_view<T, U>>::type

#            if nssv_BETWEEN(nssv_COMPILER_MSVC_VERSION, 140, 150)
#                define nssv_MSVC_ORDER(x) , int = x
#            else
#                define nssv_MSVC_ORDER(x) /*, int=x*/
#            endif

    // ==

    template <class CharT, class Traits nssv_MSVC_ORDER(1)>
    nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
                                   nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept
    {
        return lhs.compare(rhs) == 0;
    }

    template <class CharT, class Traits nssv_MSVC_ORDER(2)>
    nssv_constexpr bool operator==(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.size() == rhs.size() && lhs.compare(rhs) == 0;
    }

    // !=

    template <class CharT, class Traits nssv_MSVC_ORDER(1)>
    nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
                                   nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept
    {
        return lhs.size() != rhs.size() || lhs.compare(rhs) != 0;
    }

    template <class CharT, class Traits nssv_MSVC_ORDER(2)>
    nssv_constexpr bool operator!=(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) != 0;
    }

    // <

    template <class CharT, class Traits nssv_MSVC_ORDER(1)>
    nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
                                  nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept
    {
        return lhs.compare(rhs) < 0;
    }

    template <class CharT, class Traits nssv_MSVC_ORDER(2)>
    nssv_constexpr bool operator<(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
                                  basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) < 0;
    }

    // <=

    template <class CharT, class Traits nssv_MSVC_ORDER(1)>
    nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
                                   nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept
    {
        return lhs.compare(rhs) <= 0;
    }

    template <class CharT, class Traits nssv_MSVC_ORDER(2)>
    nssv_constexpr bool operator<=(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) <= 0;
    }

    // >

    template <class CharT, class Traits nssv_MSVC_ORDER(1)>
    nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
                                  nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept
    {
        return lhs.compare(rhs) > 0;
    }

    template <class CharT, class Traits nssv_MSVC_ORDER(2)>
    nssv_constexpr bool operator>(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
                                  basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) > 0;
    }

    // >=

    template <class CharT, class Traits nssv_MSVC_ORDER(1)>
    nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
                                   nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept
    {
        return lhs.compare(rhs) >= 0;
    }

    template <class CharT, class Traits nssv_MSVC_ORDER(2)>
    nssv_constexpr bool operator>=(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
                                   basic_string_view<CharT, Traits> rhs) nssv_noexcept
    {
        return lhs.compare(rhs) >= 0;
    }

#            undef nssv_MSVC_ORDER
#            undef nssv_BASIC_STRING_VIEW_I

#        endif // compiler-dependent approach to comparisons

    // 24.4.4 Inserters and extractors:

    namespace detail {

    template <class Stream>
    void write_padding(Stream& os, std::streamsize n)
    {
        for (std::streamsize i = 0; i < n; ++i)
            os.rdbuf()->sputc(os.fill());
    }

    template <class Stream, class View>
    Stream& write_to_stream(Stream& os, View const& sv)
    {
        typename Stream::sentry sentry(os);

        if (!os) return os;

        const std::streamsize length = static_cast<std::streamsize>(sv.length());

        // Whether, and how, to pad:
        const bool pad = (length < os.width());
        const bool left_pad =
            pad && (os.flags() & std::ios_base::adjustfield) == std::ios_base::right;

        if (left_pad) write_padding(os, os.width() - length);

        // Write span characters:
        os.rdbuf()->sputn(sv.begin(), length);

        if (pad && !left_pad) write_padding(os, os.width() - length);

        // Reset output stream width:
        os.width(0);

        return os;
    }

    } // namespace detail

    template <class CharT, class Traits>
    std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os,
                                                  basic_string_view<CharT, Traits> sv)
    {
        return detail::write_to_stream(os, sv);
    }

    // Several typedefs for common character types are provided:

    typedef basic_string_view<char> string_view;
    typedef basic_string_view<wchar_t> wstring_view;
#        if nssv_HAVE_WCHAR16_T
    typedef basic_string_view<char16_t> u16string_view;
    typedef basic_string_view<char32_t> u32string_view;
#        endif

    } // namespace sv_lite
} // namespace rapidfuzz::sv_lite

//
// 24.4.6 Suffix for basic_string_view literals:
//

#        if nssv_HAVE_USER_DEFINED_LITERALS

namespace rapidfuzz {
nssv_inline_ns namespace literals
{
    nssv_inline_ns namespace string_view_literals
    {

#            if nssv_CONFIG_STD_SV_OPERATOR && nssv_HAVE_STD_DEFINED_LITERALS

        nssv_constexpr rapidfuzz::sv_lite::string_view operator"" sv(const char* str, size_t len)
            nssv_noexcept // (1)
        {
            return rapidfuzz::sv_lite::string_view{str, len};
        }

        nssv_constexpr rapidfuzz::sv_lite::u16string_view operator"" sv(
            const char16_t* str, size_t len) nssv_noexcept // (2)
        {
            return rapidfuzz::sv_lite::u16string_view{str, len};
        }

        nssv_constexpr rapidfuzz::sv_lite::u32string_view operator"" sv(
            const char32_t* str, size_t len) nssv_noexcept // (3)
        {
            return rapidfuzz::sv_lite::u32string_view{str, len};
        }

        nssv_constexpr rapidfuzz::sv_lite::wstring_view operator"" sv(
            const wchar_t* str, size_t len) nssv_noexcept // (4)
        {
            return rapidfuzz::sv_lite::wstring_view{str, len};
        }

#            endif // nssv_CONFIG_STD_SV_OPERATOR && nssv_HAVE_STD_DEFINED_LITERALS

#            if nssv_CONFIG_USR_SV_OPERATOR

        nssv_constexpr rapidfuzz::sv_lite::string_view operator"" _sv(const char* str, size_t len)
            nssv_noexcept // (1)
        {
            return rapidfuzz::sv_lite::string_view{str, len};
        }

        nssv_constexpr rapidfuzz::sv_lite::u16string_view operator"" _sv(
            const char16_t* str, size_t len) nssv_noexcept // (2)
        {
            return rapidfuzz::sv_lite::u16string_view{str, len};
        }

        nssv_constexpr rapidfuzz::sv_lite::u32string_view operator"" _sv(
            const char32_t* str, size_t len) nssv_noexcept // (3)
        {
            return rapidfuzz::sv_lite::u32string_view{str, len};
        }

        nssv_constexpr rapidfuzz::sv_lite::wstring_view operator"" _sv(
            const wchar_t* str, size_t len) nssv_noexcept // (4)
        {
            return rapidfuzz::sv_lite::wstring_view{str, len};
        }

#            endif // nssv_CONFIG_USR_SV_OPERATOR
    }
}
} // namespace rapidfuzz

#        endif

//
// Extensions for std::string:
//

#        if nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS

namespace rapidfuzz {
namespace sv_lite {

// Exclude MSVC 14 (19.00): it yields ambiguous to_string():

#            if nssv_CPP11_OR_GREATER && nssv_COMPILER_MSVC_VERSION != 140

template <class CharT, class Traits, class Allocator = std::allocator<CharT>>
std::basic_string<CharT, Traits, Allocator> to_string(basic_string_view<CharT, Traits> v,
                                                      Allocator const& a = Allocator())
{
    return std::basic_string<CharT, Traits, Allocator>(v.begin(), v.end(), a);
}

#            else

template <class CharT, class Traits>
std::basic_string<CharT, Traits> to_string(basic_string_view<CharT, Traits> v)
{
    return std::basic_string<CharT, Traits>(v.begin(), v.end());
}

template <class CharT, class Traits, class Allocator>
std::basic_string<CharT, Traits, Allocator> to_string(basic_string_view<CharT, Traits> v,
                                                      Allocator const& a)
{
    return std::basic_string<CharT, Traits, Allocator>(v.begin(), v.end(), a);
}

#            endif // nssv_CPP11_OR_GREATER

template <class CharT, class Traits, class Allocator>
basic_string_view<CharT, Traits>
to_string_view(std::basic_string<CharT, Traits, Allocator> const& s)
{
    return basic_string_view<CharT, Traits>(s.data(), s.size());
}

} // namespace sv_lite
} // namespace rapidfuzz

#        endif // nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS

//
// make types and algorithms available in namespace rapidfuzz:
//

namespace rapidfuzz {

using sv_lite::basic_string_view;
using sv_lite::string_view;
using sv_lite::wstring_view;

#        if nssv_HAVE_WCHAR16_T
using sv_lite::u16string_view;
#        endif
#        if nssv_HAVE_WCHAR32_T
using sv_lite::u32string_view;
#        endif

// literal "sv"

using sv_lite::operator==;
using sv_lite::operator!=;
using sv_lite::operator<;
using sv_lite::operator<=;
using sv_lite::operator>;
using sv_lite::operator>=;

using sv_lite::operator<<;

#        if nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
using sv_lite::to_string;
using sv_lite::to_string_view;
#        endif

} // namespace rapidfuzz

// 24.4.5 Hash support (C++11):

// Note: The hash value of a string view object is equal to the hash value of
// the corresponding string object.

#        if nssv_HAVE_STD_HASH

#            include <functional>

namespace std {

template <>
struct hash<rapidfuzz::string_view> {
public:
    std::size_t operator()(rapidfuzz::string_view v) const nssv_noexcept
    {
        return std::hash<std::string>()(std::string(v.data(), v.size()));
    }
};

template <>
struct hash<rapidfuzz::wstring_view> {
public:
    std::size_t operator()(rapidfuzz::wstring_view v) const nssv_noexcept
    {
        return std::hash<std::wstring>()(std::wstring(v.data(), v.size()));
    }
};

template <>
struct hash<rapidfuzz::u16string_view> {
public:
    std::size_t operator()(rapidfuzz::u16string_view v) const nssv_noexcept
    {
        return std::hash<std::u16string>()(std::u16string(v.data(), v.size()));
    }
};

template <>
struct hash<rapidfuzz::u32string_view> {
public:
    std::size_t operator()(rapidfuzz::u32string_view v) const nssv_noexcept
    {
        return std::hash<std::u32string>()(std::u32string(v.data(), v.size()));
    }
};

} // namespace std

#        endif // nssv_HAVE_STD_HASH

nssv_RESTORE_WARNINGS()

#    endif // nssv_HAVE_STD_STRING_VIEW
#endif     // NONSTD_SV_LITE_H_INCLUDED