C++ string_view::cbegin方法代码示例

void test_strview_basics(const string_view& sv, const char *p, size_t n) {
    ASSERT_EQ(p, sv.data());
    ASSERT_EQ(n, sv.size());
    ASSERT_EQ(n, sv.length());
    ASSERT_EQ((n == 0), sv.empty());

    ASSERT_EQ(p, sv.cbegin());
    ASSERT_EQ(p, sv.begin());
    ASSERT_EQ(p + n, sv.cend());
    ASSERT_EQ(p + n, sv.end());

    using reviter_t = std::reverse_iterator<string_view::const_iterator>;

    ASSERT_EQ(reviter_t(sv.end()),    sv.rbegin());
    ASSERT_EQ(reviter_t(sv.begin()),  sv.rend());
    ASSERT_EQ(reviter_t(sv.cend()),   sv.crbegin());
    ASSERT_EQ(reviter_t(sv.cbegin()), sv.crend());

    for (size_t i = 0; i < n; ++i) {
        ASSERT_EQ(p[i], sv[i]);
        ASSERT_EQ(p[i], sv.at(i));
    }
    ASSERT_THROW(sv.at(n), std::out_of_range);
    ASSERT_THROW(sv.at(string_view::npos), std::out_of_range);

    if (n > 0) {
        ASSERT_EQ(p,         &(sv.front()));
        ASSERT_EQ(p + (n-1), &(sv.back()));
        ASSERT_EQ(p[0],        sv.front());
        ASSERT_EQ(p[n-1],      sv.back());
    }
}

size_t find_icase(string_view const Str, wchar_t const What, size_t Pos)
{
	if (Pos >= Str.size())
		return Str.npos;

	const auto It = std::find_if(Str.cbegin() + Pos, Str.cend(), [&](wchar_t const Char) { return equal_icase_t{}(What, Char); });
	return It == Str.cend() ? Str.npos : It - Str.cbegin();
}

int main()
{
    typedef std::experimental::string_view    string_view;
    typedef std::experimental::u16string_view u16string_view;
    typedef std::experimental::u32string_view u32string_view;
    typedef std::experimental::wstring_view   wstring_view;

    test(string_view   ());
    test(u16string_view());
    test(u32string_view());
    test(wstring_view  ());
    test(string_view   ( "123"));
    test(wstring_view  (L"123"));
#if __cplusplus >= 201103L
    test(u16string_view{u"123"});
    test(u32string_view{U"123"});
#endif

#if _LIBCPP_STD_VER > 11
    {
    constexpr string_view       sv { "123", 3 };
    constexpr u16string_view u16sv {u"123", 3 };
    constexpr u32string_view u32sv {U"123", 3 };
    constexpr wstring_view     wsv {L"123", 3 };
    
    static_assert (    *sv.begin() ==    sv[0], "" );
    static_assert ( *u16sv.begin() == u16sv[0], "" );
    static_assert ( *u32sv.begin() == u32sv[0], "" );
    static_assert (   *wsv.begin() ==   wsv[0], "" );

    static_assert (    *sv.cbegin() ==    sv[0], "" );
    static_assert ( *u16sv.cbegin() == u16sv[0], "" );
    static_assert ( *u32sv.cbegin() == u32sv[0], "" );
    static_assert (   *wsv.cbegin() ==   wsv[0], "" );
    }
#endif
}

std::list<CommandLine::segment> CommandLine::GetPrompt()
{
	FN_RETURN_TYPE(CommandLine::GetPrompt) Result;
	int NewPromptSize = DEFAULT_CMDLINE_WIDTH;

	const auto& PrefixColor = colors::PaletteColorToFarColor(COL_COMMANDLINEPREFIX);

	if (Global->Opt->CmdLine.UsePromptFormat)
	{
		const string_view Format = Global->Opt->CmdLine.strPromptFormat.Get();
		auto Tail = Format.cbegin();
		auto Color = PrefixColor;
		FOR_CONST_RANGE(Format, Iterator)
		{
			bool Stop;
			auto NewColor = PrefixColor;
			const auto NextIterator = colors::ExtractColorInNewFormat(Iterator, Format.cend(), NewColor, Stop);
			if (NextIterator == Iterator)
			{
				if (Stop)
					break;
				continue;
			}

			if (Iterator != Format.cbegin())
			{
				Result.emplace_back(segment{ string(Tail, Iterator), Color });
			}
			Iterator = NextIterator;
			Tail = Iterator;
			Color = NewColor;
		}
		Result.emplace_back(segment{ string(Tail, Format.cend()), Color });

		for (auto Iterator = Result.begin(); Iterator != Result.end(); ++Iterator)
		{
			const auto strExpandedDestStr = os::env::expand(Iterator->Text);
			Iterator->Text.clear();
			static const std::pair<wchar_t, wchar_t> ChrFmt[] =
			{
				{L'A', L'&'},   // $A - & (Ampersand)
				{L'B', L'|'},   // $B - | (pipe)
				{L'C', L'('},   // $C - ( (Left parenthesis)
				{L'F', L')'},   // $F - ) (Right parenthesis)
				{L'G', L'>'},   // $G - > (greater-than sign)
				{L'L', L'<'},   // $L - < (less-than sign)
				{L'Q', L'='},   // $Q - = (equal sign)
				{L'S', L' '},   // $S - (space)
				{L'$', L'$'},   // $$ - $ (dollar sign)
			};

			FOR_CONST_RANGE(strExpandedDestStr, it)
			{
				auto& strDestStr = Iterator->Text;

				if (*it == L'$' && it + 1 != strExpandedDestStr.cend())
				{
					const auto Chr = upper(*++it);

					const auto ItemIterator = std::find_if(CONST_RANGE(ChrFmt, Item)
					{
						return Item.first == Chr;
					});

					if (ItemIterator != std::cend(ChrFmt))
					{
						strDestStr += ItemIterator->second;
					}
					else
					{
						const auto& AddCollapsible = [&](string&& Str)
						{
							if (strDestStr.empty())
							{
								strDestStr = std::move(Str);
								Iterator->Collapsible = true;
							}
							else
							{
								Iterator = Result.insert(std::next(Iterator), segment{ std::move(Str), Iterator->Colour, true });
							}

							// No need to introduce a new segment if we're at the very end
							if (std::next(Iterator) != Result.end() && std::next(it) != strExpandedDestStr.cend())
							{
								Iterator = Result.insert(std::next(Iterator), segment{ {}, Iterator->Colour, false });
							}
						};

						switch (Chr)
						{
								/* эти не реaлизованы
								$E - Escape code (ASCII code 27)
								$V - Windows version number
								$_ - Carriage return and linefeed
								*/
							case L'M': // $M - Отображение полного имени удаленного диска, связанного с именем текущего диска, или пустой строки, если текущий диск не является сетевым.
							{
								string strTemp;
								if (DriveLocalToRemoteName(DRIVE_UNKNOWN, m_CurDir[0], strTemp))
//.........这里部分代码省略.........