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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0+ OR GPL-3.0 WITH Qt-GPL-exception-1.0
#pragma once
#include "smallstringfwd.h"
#include "smallstringiterator.h"
#include <QString>
#include <cstring>
#include <string>
#include <string_view>
namespace Utils {
template <typename String>
using enable_if_has_char_data_pointer = typename std::enable_if_t<
std::is_same<
std::remove_const_t<
std::remove_pointer_t<
decltype(std::declval<const String>().data())
>
>, char>::value
, int>;
class SmallStringView : public std::string_view
{
public:
using std::string_view::string_view;
constexpr SmallStringView(const_iterator begin, const_iterator end) noexcept
: std::string_view{std::addressof(*begin), static_cast<std::size_t>(std::distance(begin, end))}
{}
#ifdef Q_CC_MSVC
constexpr SmallStringView(const char *const begin, const char *const end) noexcept
: std::string_view{begin, static_cast<std::size_t>(std::distance(begin, end))}
{}
#endif
template<typename String, typename Utils::enable_if_has_char_data_pointer<String> = 0>
constexpr SmallStringView(const String &string) noexcept
: std::string_view{string.data(), static_cast<std::size_t>(string.size())}
{}
static constexpr SmallStringView fromUtf8(const char *const characterPointer)
{
return SmallStringView(characterPointer);
}
constexpr size_type isEmpty() const noexcept { return empty(); }
constexpr
SmallStringView mid(size_type position) const noexcept
{
return SmallStringView(data() + position, size() - position);
}
constexpr
SmallStringView mid(size_type position, size_type length) const noexcept
{
return SmallStringView(data() + position, length);
}
constexpr20 operator std::string() const { return std::string(data(), size()); }
explicit operator QString() const
{
return QString::fromUtf8(data(), int(size()));
}
explicit operator QByteArray() const
{
return QByteArray(data(), int(size()));
}
constexpr bool startsWith(SmallStringView subStringToSearch) const noexcept
{
if (size() >= subStringToSearch.size())
return !std::char_traits<char>::compare(data(),
subStringToSearch.data(),
subStringToSearch.size());
return false;
}
constexpr bool startsWith(char characterToSearch) const noexcept
{
return *begin() == characterToSearch;
}
constexpr bool endsWith(SmallStringView ending) const noexcept
{
return size() >= ending.size() && std::equal(ending.rbegin(), ending.rend(), rbegin());
}
};
constexpr bool operator!=(SmallStringView first, SmallStringView second) noexcept
{
return std::string_view{first} != std::string_view{second};
}
constexpr bool operator==(SmallStringView first, SmallStringView second) noexcept
{
return std::string_view{first} == std::string_view{second};
}
constexpr bool operator<(SmallStringView first, SmallStringView second) noexcept
{
return std::string_view{first} < std::string_view{second};
}
constexpr bool operator>(SmallStringView first, SmallStringView second) noexcept
{
return std::string_view{first} > std::string_view{second};
}
constexpr bool operator<=(SmallStringView first, SmallStringView second) noexcept
{
return std::string_view{first} <= std::string_view{second};
}
constexpr bool operator>=(SmallStringView first, SmallStringView second) noexcept
{
return std::string_view{first} >= std::string_view{second};
}
constexpr int compare(SmallStringView first, SmallStringView second) noexcept
{
return first.compare(second);
}
namespace Internal {
constexpr int reverse_memcmp(const char *first, const char *second, size_t n)
{
const char *currentFirst = first + n - 1;
const char *currentSecond = second + n - 1;
while (n > 0) {
// If the current characters differ, return an appropriately signed
// value; otherwise, keep searching backwards
int difference = *currentFirst - *currentSecond;
if (difference != 0)
return difference;
--currentFirst;
--currentSecond;
--n;
}
return 0;
}
} // namespace Internal
constexpr int reverseCompare(SmallStringView first, SmallStringView second) noexcept
{
int difference = Internal::reverse_memcmp(first.data(), second.data(), first.size());
if (difference == 0)
return int(first.size()) - int(second.size());
return difference;
}
} // namespace Utils
constexpr Utils::SmallStringView operator""_sv(const char *const string, size_t size)
{
return Utils::SmallStringView(string, size);
}
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