\inmodule QtCore More...

#include <qanystringview.h>

Collaboration diagram for QAnyStringView:

Public Types
typedef qptrdiff	difference_type
	Alias for {std::ptrdiff_t}.

typedef qsizetype	size_type
	Alias for qsizetype.

Public Member Functions
constexpr	QAnyStringView () noexcept
	Constructs a null string view.

constexpr	QAnyStringView (std::nullptr_t) noexcept
	Constructs a null string view.

template<typename Char , if_compatible_char< Char > = true>
constexpr	QAnyStringView (const Char *str, qsizetype len)
	Constructs a string view on str with length len.

template<typename Char , if_compatible_char< Char > = true>
constexpr	QAnyStringView (const Char f, const Char l)
	Constructs a string view on first with length (last - first).

template<typename Pointer , if_compatible_pointer< Pointer > = true>
constexpr	QAnyStringView (const Pointer &str) noexcept

	QAnyStringView (const QByteArray &str) noexcept
	Constructs a string view on str.

	QAnyStringView (const QString &str) noexcept
	Constructs a string view on str.

constexpr	QAnyStringView (QLatin1StringView str) noexcept

template<typename Container , if_compatible_container< Container > = true>
constexpr Q_ALWAYS_INLINE	QAnyStringView (const Container &c) noexcept

template<typename Container , if_convertible_to< QString, Container > = true>
constexpr	QAnyStringView (Container &&c, QtPrivate::wrapped_t< Container, QString > &&capacity={})

template<typename Container , if_convertible_to< QByteArray, Container > = true>
constexpr	QAnyStringView (Container &&c, QtPrivate::wrapped_t< Container, QByteArray > &&capacity={})

template<typename Char , if_compatible_char< Char > = true>
constexpr	QAnyStringView (const Char &c) noexcept

constexpr	QAnyStringView (const QChar &c) noexcept

template<typename Char , typename Container = decltype(QChar::fromUcs4(U'x')), std::enable_if_t< std::is_same_v< Char, char32_t >, bool > = true>
constexpr	QAnyStringView (Char c, Container &&capacity={})

constexpr	QAnyStringView (QStringView v) noexcept

template<bool UseChar8T>
constexpr	QAnyStringView (QBasicUtf8StringView< UseChar8T > v) noexcept

template<typename Visitor >
constexpr decltype(auto)	visit (Visitor &&v) const
	Calls v with either a QUtf8StringView, QLatin1String, or QStringView, depending on the encoding of the string data this string-view references.

constexpr QAnyStringView	mid (qsizetype pos, qsizetype n=-1) const

constexpr QAnyStringView	left (qsizetype n) const

constexpr QAnyStringView	right (qsizetype n) const

constexpr QAnyStringView	sliced (qsizetype pos) const

constexpr QAnyStringView	sliced (qsizetype pos, qsizetype n) const

constexpr QAnyStringView	first (qsizetype n) const

constexpr QAnyStringView	last (qsizetype n) const

constexpr QAnyStringView	chopped (qsizetype n) const

constexpr void	truncate (qsizetype n)

constexpr void	chop (qsizetype n)

QString	toString () const
	Returns a deep copy of this string view's data as a QString.

constexpr qsizetype	size () const noexcept
	Returns the size of this string view, in the encoding's code points.

constexpr const void *	data () const noexcept
	Returns a const pointer to the first character in the string view.

constexpr QChar	front () const
	Returns the first character in the string view.

constexpr QChar	back () const
	Returns the last character in the string view.

constexpr bool	empty () const noexcept
	Returns whether this string view is empty - that is, whether {size() == 0}.

constexpr qsizetype	size_bytes () const noexcept
	Returns the size of this string view, but in bytes, not code-points.

constexpr bool	isNull () const noexcept
	Returns whether this string view is null - that is, whether {data() == nullptr}.

constexpr bool	isEmpty () const noexcept
	Returns whether this string view is empty - that is, whether {size() == 0}.

constexpr qsizetype	length () const noexcept
	Same as size().

template<typename Visitor >
constexpr decltype(auto)	visit (Visitor &&v) const

Static Public Member Functions
template<typename Char , size_t Size, if_compatible_char< Char > = true>
static constexpr QAnyStringView	fromArray (const Char(&string)[Size]) noexcept

static Q_CORE_EXPORT int	compare (QAnyStringView lhs, QAnyStringView rhs, Qt::CaseSensitivity cs=Qt::CaseSensitive) noexcept
	Compares the string view lhs with the string view rhs and returns a negative integer if lhs is less than rhs, a positive integer if it is greater than rhs, and zero if they are equal.

static Q_CORE_EXPORT bool	equal (QAnyStringView lhs, QAnyStringView rhs) noexcept

Static Public Attributes
static constexpr bool	detects_US_ASCII_at_compile_time

Friends
class	::tst_QAnyStringView

bool	comparesEqual (const QAnyStringView &lhs, const QAnyStringView &rhs) noexcept

Qt::strong_ordering	compareThreeWay (const QAnyStringView &lhs, const QAnyStringView &rhs) noexcept

Q_CORE_EXPORT friend QDebug	operator<< (QDebug d, QAnyStringView s)

Related Symbols
(Note that these are not member symbols.)
QString	convertToQString (QAnyStringView string)

Detailed Description

\inmodule QtCore

Since: 6.0

The QAnyStringView class provides a unified view on Latin-1, UTF-8, or UTF-16 strings with a read-only subset of the QString API. \reentrant

\compares strong \compareswith strong char16_t QChar {const char16_t *} {const char *} \ QByteArray QByteArrayView QString QStringView QUtf8StringView \ QLatin1StringView \endcompareswith

A QAnyStringView references a contiguous portion of a string it does not own. It acts as an interface type to all kinds of strings, without the need to construct a QString first.

Unlike QStringView and QUtf8StringView, QAnyStringView can hold strings of any of the following encodings: UTF-8, UTF-16, and Latin-1. The latter is supported because Latin-1, unlike UTF-8, can be efficiently compared to UTF-16 data: a length mismatch already means the strings cannot be equal. This is not true for UTF-8/UTF-16 comparisons, because UTF-8 is a variable-length encoding.

The string may be represented as an array (or an array-compatible data-structure such as QString, std::basic_string, etc.) of char, char8_t, QChar, ushort, char16_t or (on platforms, such as Windows, where it is a 16-bit type) wchar_t.

QAnyStringView is designed as an interface type; its main use-case is as a function parameter type. When QAnyStringViews are used as automatic variables or data members, care must be taken to ensure that the referenced string data (for example, owned by a QString) outlives the QAnyStringView on all code paths, lest the string view ends up referencing deleted data.

When used as an interface type, QAnyStringView allows a single function to accept a wide variety of string data sources. One function accepting QAnyStringView thus replaces five function overloads (taking QString, {(const QChar*, qsizetype)}, QUtf8StringView, QLatin1StringView (but see above), and QChar), while at the same time enabling even more string data sources to be passed to the function, such as {u8"Hello World"}, a char8_t string literal.

Like elsewhere in Qt, QAnyStringView assumes char data is encoded in UTF-8, unless it is presented as a QLatin1StringView.

Since Qt 6.4, however, UTF-8 string literals that are pure US-ASCII are automatically stored as Latin-1. This is a compile-time check with no runtime overhead. The feature requires compiling in C++20, or with a recent GCC.

QAnyStringViews should be passed by value, not by reference-to-const:

void myfun1(QAnyStringView sv); // preferred

void myfun2(const QAnyStringView &sv); // compiles and works, but slower

QAnyStringView can also be used as the return value of a function, but this is not recommended. QUtf8StringView or QStringView are better suited as function return values. If you call a function returning QAnyStringView, take extra care to not keep the QAnyStringView around longer than the function promises to keep the referenced string data alive. If in doubt, obtain a strong reference to the data by calling toString() to convert the QAnyStringView into a QString.

QAnyStringView is a {Literal Type}.

Definition at line 32 of file qanystringview.h.

Member Typedef Documentation

◆ difference_type

QAnyStringView::difference_type

Alias for {std::ptrdiff_t}.

Provided for compatibility with the STL.

Definition at line 35 of file qanystringview.h.

◆ size_type

QAnyStringView::size_type

Alias for qsizetype.

Provided for compatibility with the STL.

Definition at line 36 of file qanystringview.h.

Constructor & Destructor Documentation

◆ QAnyStringView() [1/16]

QAnyStringView::QAnyStringView ( )

inlineconstexprnoexcept

Constructs a null string view.

See also: isNull()

Definition at line 150 of file qanystringview.h.

Referenced by fromArray(), and mid().

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◆ QAnyStringView() [2/16]

QAnyStringView::QAnyStringView ( std::nullptr_t )

inlineconstexprnoexcept

Constructs a null string view.

See also: isNull()

Definition at line 152 of file qanystringview.h.

◆ QAnyStringView() [3/16]

template<typename Char , if_compatible_char< Char > = true>

template< typename Char, QAnyStringView::if_compatible_char< Char >=true > QAnyStringView::QAnyStringView	(	const Char *	str,
		qsizetype	len )

inlineconstexpr

Constructs a string view on str with length len.

The range {[str,len)} must remain valid for the lifetime of this string view object.

Passing \nullptr as str is safe if len is 0, too, and results in a null string view.

The behavior is undefined if len is negative or, when positive, if str is \nullptr.

This constructor only participates in overload resolution if Char is a compatible character type.

See also: isNull(), {Compatible Character Types}

Definition at line 156 of file qanystringview.h.

◆ QAnyStringView() [4/16]

template<typename Char , if_compatible_char< Char > = true>

template< typename Char, QAnyStringView::if_compatible_char< Char >=true > QAnyStringView::QAnyStringView	(	const Char *	first,
		const Char *	last )

inlineconstexpr

Constructs a string view on first with length (last - first).

The range {[first,last)} must remain valid for the lifetime of this string view object.

Passing \nullptr as first is safe if last is \nullptr, too, and results in a null string view.

The behavior is undefined if last precedes first, or first is \nullptr and last is not.

This constructor only participates in overload resolution if Char is a compatible character type.

See also: isNull(), {Compatible Character Types}

Definition at line 162 of file qanystringview.h.

◆ QAnyStringView() [5/16]

template<typename Pointer , if_compatible_pointer< Pointer > = true>

constexpr QAnyStringView::QAnyStringView ( const Pointer & str )

inlineconstexprnoexcept

Definition at line 174 of file qanystringview.h.

References str.

◆ QAnyStringView() [6/16]

QAnyStringView::QAnyStringView ( const QByteArray & str )

inlinenoexcept

Constructs a string view on str.

The data in str is interpreted as UTF-8.

{str.data()} must remain valid for the lifetime of this string view object.

The string view will be null if and only if {str.isNull()}.

Definition at line 1213 of file qstring.h.

References QString::data(), QString::isNull(), nullptr, QString::size(), and str.

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◆ QAnyStringView() [7/16]

QAnyStringView::QAnyStringView ( const QString & str )

inlinenoexcept

Constructs a string view on str.

{str.data()} must remain valid for the lifetime of this string view object.

The string view will be null if and only if {str.isNull()}.

Definition at line 1215 of file qstring.h.

References QString::data(), QString::isNull(), nullptr, QString::size(), and str.

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◆ QAnyStringView() [8/16]

constexpr QAnyStringView::QAnyStringView ( QLatin1StringView str )

inlineconstexprnoexcept

Definition at line 93 of file qstring.h.

References QString::data(), and str.

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◆ QAnyStringView() [9/16]

template<typename Container , if_compatible_container< Container > = true>

constexpr Q_ALWAYS_INLINE QAnyStringView::QAnyStringView ( const Container & c )

inlineconstexprnoexcept

Definition at line 184 of file qanystringview.h.

◆ QAnyStringView() [10/16]

template<typename Container , if_convertible_to< QString, Container > = true>

constexpr QAnyStringView::QAnyStringView	(	Container &&	c,
		QtPrivate::wrapped_t< Container, QString > &&	capacity = {} )

inlineconstexpr

Definition at line 188 of file qanystringview.h.

◆ QAnyStringView() [11/16]

template<typename Container , if_convertible_to< QByteArray, Container > = true>

constexpr QAnyStringView::QAnyStringView	(	Container &&	c,
		QtPrivate::wrapped_t< Container, QByteArray > &&	capacity = {} )

inlineconstexpr

Definition at line 193 of file qanystringview.h.

◆ QAnyStringView() [12/16]

template<typename Char , if_compatible_char< Char > = true>

constexpr QAnyStringView::QAnyStringView ( const Char & c )

inlineconstexprnoexcept

Definition at line 198 of file qanystringview.h.

◆ QAnyStringView() [13/16]

constexpr QAnyStringView::QAnyStringView ( const QChar & c )

inlineconstexprnoexcept

Definition at line 200 of file qanystringview.h.

◆ QAnyStringView() [14/16]

template<typename Char , typename Container = decltype(QChar::fromUcs4(U'x')), std::enable_if_t< std::is_same_v< Char, char32_t >, bool > = true>

constexpr QAnyStringView::QAnyStringView	(	Char	c,
		Container &&	capacity = {} )

inlineconstexpr

Definition at line 205 of file qanystringview.h.

◆ QAnyStringView() [15/16]

constexpr QAnyStringView::QAnyStringView ( QStringView v )

inlineconstexprnoexcept

Definition at line 208 of file qanystringview.h.

◆ QAnyStringView() [16/16]

template<bool UseChar8T>

constexpr QAnyStringView::QAnyStringView ( QBasicUtf8StringView< UseChar8T > v )

inlineconstexprnoexcept

Definition at line 212 of file qanystringview.h.

Member Function Documentation

◆ back()

constexpr QChar QAnyStringView::back ( ) const

constexpr

Returns the last character in the string view.

This function is provided for STL compatibility.

Warning: Calling this function on an empty string view constitutes undefined behavior.

See also: front(), {Sizes and Sub-Strings}

Definition at line 122 of file qstring.h.

References visit().

Referenced by ResolvedTypeAlias::ResolvedTypeAlias().

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◆ chop()

QAnyStringView::chop ( qsizetype n )

inlineconstexpr

Since: 6.5

Truncates this string view by n code points.

Same as {*this = first(size() - n)}.

Note: The behavior is undefined when n < 0 or n > size().

See also: sliced(), first(), last(), chopped(), truncate(), {Sizes and Sub-Strings}

Definition at line 258 of file qanystringview.h.

◆ chopped()

QAnyStringView::chopped ( qsizetype n ) const

inlineconstexpr

\fn QAnyStringView::sliced(qsizetype pos, qsizetype n) const
\since 6.5

Returns a string view containing \a n code points of this string view,
starting at position \a pos.

! [UB-sliced-index-length]

Note

The behavior is undefined when pos < 0, n < 0, or pos + n > size(). ! [UB-sliced-index-length]

\sa first(), last(), chopped(), chop(), truncate(), {Sizes and Sub-Strings}

\fn QAnyStringView::sliced(qsizetype pos) const
\since 6.5

Returns a string view starting at position \a pos in this object,
and extending to its end.

! [UB-sliced-index-only]

Note

The behavior is undefined when pos < 0 or pos > size(). ! [UB-sliced-index-only]

\sa first(), last(), chopped(), chop(), truncate(), {Sizes and Sub-Strings}

Since: 6.5

Returns the substring of length size() - n starting at the beginning of this object.

Same as {first(size() - n)}.

Note: The behavior is undefined when n < 0 or n > size().

See also: sliced(), first(), last(), chop(), truncate(), {Sizes and Sub-Strings}

Definition at line 253 of file qanystringview.h.

References sliced().

Referenced by ResolvedTypeAlias::ResolvedTypeAlias().

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◆ compare()

int QAnyStringView::compare	(	QAnyStringView	lhs,
		QAnyStringView	rhs,
		Qt::CaseSensitivity	cs = Qt::CaseSensitive )

staticnoexcept

Compares the string view lhs with the string view rhs and returns a negative integer if lhs is less than rhs, a positive integer if it is greater than rhs, and zero if they are equal.

If cs is Qt::CaseSensitive (the default), the comparison is case sensitive; otherwise the comparison is case-insensitive.

See also: operator==(), operator<(), operator>()

Definition at line 1599 of file qstring.cpp.

References QtPrivate::compareStrings().

Referenced by QNetworkHeadersPrivate::findRawHeader(), and QCalendarRegistryCaseInsensitiveAnyStringViewLessThan::operator()().

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◆ data()

const void * QAnyStringView::data ( ) const

inlineconstexprnoexcept

Returns a const pointer to the first character in the string view.

Note: The character array represented by the return value is not null-terminated.

See also: size_bytes()

Definition at line 266 of file qanystringview.h.

References m_data.

◆ empty()

bool QAnyStringView::empty ( ) const

inlineconstexprnoexcept

Returns whether this string view is empty - that is, whether {size() == 0}.

This function is provided for STL compatibility.

See also: isEmpty(), isNull(), size()

Definition at line 284 of file qanystringview.h.

Referenced by isEmpty().

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◆ equal()

bool QAnyStringView::equal	(	QAnyStringView	lhs,
		QAnyStringView	rhs )

staticnoexcept

Definition at line 1448 of file qstring.cpp.

References QtPrivate::equalStrings().

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◆ first()

QAnyStringView::first ( qsizetype n ) const

inlineconstexpr

Since: 6.5

Returns a string view that contains the first n code points of this string view.

Note: The behavior is undefined when n < 0 or n > size().

See also: last(), sliced(), chopped(), chop(), truncate(), {Sizes and Sub-Strings}

Definition at line 249 of file qanystringview.h.

References sliced().

Referenced by QQmlJSRegisterContent::descriptiveName().

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◆ fromArray()

template<typename Char , size_t Size, if_compatible_char< Char > = true>

static constexpr QAnyStringView QAnyStringView::fromArray ( const Char(&) string[Size] )

inlinestaticconstexprnoexcept

Definition at line 216 of file qanystringview.h.

References QAnyStringView().

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◆ front()

constexpr QChar QAnyStringView::front ( ) const

constexpr

Returns the first character in the string view.

This function is provided for STL compatibility.

Warning: Calling this function on an empty string view constitutes undefined behavior.

See also: back(), {Sizes and Sub-Strings}

Definition at line 118 of file qstring.h.

References visit().

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◆ isEmpty()

bool QAnyStringView::isEmpty ( ) const

inlineconstexprnoexcept

Returns whether this string view is empty - that is, whether {size() == 0}.

This function is provided for compatibility with other Qt containers.

See also: empty(), isNull(), size()

Definition at line 292 of file qanystringview.h.

References empty().

Referenced by QmlTypesClassDescription::collect(), and QQmlSA::PassManagerPrivate::registerPropertyPass().

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◆ isNull()

bool QAnyStringView::isNull ( ) const

inlineconstexprnoexcept

Returns whether this string view is null - that is, whether {data() == nullptr}.

This functions is provided for compatibility with other Qt containers.

See also: empty(), isEmpty(), size()

Definition at line 291 of file qanystringview.h.

References m_data.

◆ last()

QAnyStringView::last ( qsizetype n ) const

inlineconstexpr

Since: 6.5

Returns a string view that contains the last n code points of this string view.

Note: The behavior is undefined when n < 0 or n > size().

See also: first(), sliced(), chopped(), chop(), truncate(), {Sizes and Sub-Strings}

Definition at line 251 of file qanystringview.h.

References sliced().

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◆ left()

QAnyStringView::left ( qsizetype n ) const

inlineconstexpr

Since: 6.5

Deprecated: Use first() instead in new code.

Returns the substring of length n starting at position 0 in this object.

The entire string view is returned if n is greater than or equal to size(), or less than zero.

See also: first(), last(), sliced(), chopped(), chop(), truncate(), {Sizes and Sub-Strings}

Definition at line 231 of file qanystringview.h.

References sliced().

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◆ length()

QAnyStringView::length ( ) const

inlineconstexprnoexcept

Same as size().

This function is provided for compatibility with other Qt containers.

See also: size()

Definition at line 293 of file qanystringview.h.

◆ mid()

QAnyStringView::mid	(	qsizetype	pos,
		qsizetype	n = -1 ) const

inlineconstexpr

Since: 6.5

Returns the substring of length n starting at position pos in this object.

Deprecated: Use sliced() instead in new code.

Returns an empty string view if n exceeds the length of the string view. If there are less than n code points available in the string view starting at pos, or if n is negative (default), the function returns all code points that are available from pos.

See also: first(), last(), sliced(), chopped(), chop(), truncate(), {Sizes and Sub-Strings}

Definition at line 224 of file qanystringview.h.

References QAnyStringView(), pos, and sliced().

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◆ right()

QAnyStringView::right ( qsizetype n ) const

inlineconstexpr

Since: 6.5

Deprecated: Use last() instead in new code.

Returns the substring of length n starting at position size() - n in this object.

The entire string view is returned if n is greater than or equal to size(), or less than zero.

See also: first(), last(), sliced(), chopped(), chop(), truncate(), {Sizes and Sub-Strings}

Definition at line 238 of file qanystringview.h.

References sliced().

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◆ size()

qsizetype QAnyStringView::size ( ) const

inlineconstexprnoexcept

Returns the size of this string view, in the encoding's code points.

See also: empty(), isEmpty(), isNull(), size_bytes(), {Sizes and Sub-Strings}

Definition at line 264 of file qanystringview.h.

Referenced by Interface::Interface().

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◆ size_bytes()

QAnyStringView::size_bytes ( ) const

inlineconstexprnoexcept

Returns the size of this string view, but in bytes, not code-points.

You can use this function together with data() for hashing or serialization.

This function is provided for STL compatibility.

See also: size(), data()

Definition at line 285 of file qanystringview.h.

◆ sliced() [1/2]

constexpr QAnyStringView QAnyStringView::sliced ( qsizetype pos ) const

inlineconstexpr

Definition at line 245 of file qanystringview.h.

References pos.

Referenced by chopped(), first(), last(), left(), mid(), and right().

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◆ sliced() [2/2]

constexpr QAnyStringView QAnyStringView::sliced	(	qsizetype	pos,
		qsizetype	n ) const

inlineconstexpr

Definition at line 247 of file qanystringview.h.

References pos.

◆ toString()

QString QAnyStringView::toString ( ) const

inline

Returns a deep copy of this string view's data as a QString.

The return value will be a null QString if and only if this string view is null.

Definition at line 1218 of file qstring.h.

References QtPrivate::convertToQString().

Referenced by ForbiddenChildrenPropertyValidatorPass::addWarning(), QQmlComponentPrivate::completeLoadFromModule(), QQmlJSLogger::defaultCategories(), QQmlSA::PassManager::hasImportedModule(), QtPrivate::BindableWarnings::printUnsuitableBindableWarning(), and QQmlSA::PassManagerPrivate::registerPropertyPass().

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◆ truncate()

QAnyStringView::truncate ( qsizetype n )

inlineconstexpr

Since: 6.5

Truncates this string view to n code points.

Same as {*this = first(n)}.

Note: The behavior is undefined when n < 0 or n > size().

See also: sliced(), first(), last(), chopped(), chop(), {Sizes and Sub-Strings}

Definition at line 256 of file qanystringview.h.

◆ visit() [1/2]

template<typename Visitor >

decltype(auto) template< typename Visitor > QAnyStringView::visit ( Visitor && v ) const

inlineconstexpr

Calls v with either a QUtf8StringView, QLatin1String, or QStringView, depending on the encoding of the string data this string-view references.

This is how most functions taking QAnyStringView fork off into per-encoding functions:

void processImpl(QLatin1String s) { ~~~ }
void processImpl(QUtf8StringView s) { ~~~ }
void processImpl(QStringView s) { ~~~ }
 
void process(QAnyStringView s)
{
    s.visit([](auto s) { processImpl(s); });
}

Here, we're reusing the same name, s, for both the QAnyStringView object, as well as the lambda's parameter. This is idiomatic code and helps track the identity of the objects through visit() calls, for example in more complex situations such as

bool equal(QAnyStringView lhs, QAnyStringView rhs)
{
    // assuming operator==(QAnyStringView, QAnyStringView) didn't, yet, exist:
    return lhs.visit([rhs](auto lhs) {
        rhs.visit([lhs](auto rhs) {
            return lhs == rhs;
        });
    });
}

visit() requires that all lambda instantiations have the same return type. If they differ, you get a compile error, even if there is a common type. To fix, you can use explicit return types on the lambda, or cast in the return statements:

// wrong:
QAnyStringView firstHalf(QAnyStringView input)
{
    return input.visit([](auto input) {   // ERROR: lambdas return different types
        return input.sliced(0, input.size() / 2);
    });
}
// correct:
QAnyStringView firstHalf(QAnyStringView input)
{
    return input.visit([](auto input) -> QAnyStringView { // OK, explicit return type
        return input.sliced(0, input.size() / 2);
    });
}
// also correct:
QAnyStringView firstHalf(QAnyStringView input)
{
    return input.visit([](auto input) {
        return QAnyStringView(input.sliced(0, input.size() / 2)); // OK, cast to common type
    });
}

Referenced by back(), front(), and QAnyStringViewUtils::trimmed().

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◆ visit() [2/2]

template<typename Visitor >

constexpr decltype(auto) QAnyStringView::visit ( Visitor && v ) const

constexpr

Definition at line 104 of file qstring.h.

Friends And Related Symbol Documentation

◆ ::tst_QAnyStringView

friend class ::tst_QAnyStringView

friend

Definition at line 338 of file qanystringview.h.

◆ comparesEqual

bool comparesEqual	(	const QAnyStringView &	lhs,
		const QAnyStringView &	rhs )

friend

Definition at line 297 of file qanystringview.h.

◆ compareThreeWay

Qt::strong_ordering compareThreeWay	(	const QAnyStringView &	lhs,
		const QAnyStringView &	rhs )

friend

Definition at line 300 of file qanystringview.h.

◆ convertToQString()

QString convertToQString ( QAnyStringView string )

Since: 6.0

Returns a UTF-16 representation of string as a QString.

See also: QString::toLatin1(), QStringView::toLatin1(), QtPrivate::convertToUtf8(), QtPrivate::convertToLocal8Bit(), QtPrivate::convertToUcs4()

Definition at line 5620 of file qstring.cpp.

◆ operator<<

Q_CORE_EXPORT friend QDebug operator<<	(	QDebug	d,
		QAnyStringView	s )

friend

Definition at line 634 of file qanystringview.cpp.

Member Data Documentation

◆ detects_US_ASCII_at_compile_time

constexpr bool QAnyStringView::detects_US_ASCII_at_compile_time

inlinestaticconstexpr

Initial value:

=
 
            false

Definition at line 271 of file qanystringview.h.

◆ m_data

const void* QAnyStringView::m_data

Definition at line 333 of file qanystringview.h.

Referenced by data(), and isNull().

◆ m_data_utf16

const char16_t* QAnyStringView::m_data_utf16

Definition at line 335 of file qanystringview.h.

◆ m_data_utf8

const char* QAnyStringView::m_data_utf8

Definition at line 334 of file qanystringview.h.

The documentation for this class was generated from the following files:

qtbase/src/corelib/text/qanystringview.h (4b806d678e68c786f4be3809c72d396ae15bb04c)
qtbase/src/corelib/text/qanystringview.cpp (2bc9ad0e5dd75cf69f4a8bf94a6a917de2b4e8c4)
qtbase/src/corelib/text/qstring.cpp (f0f2a9ef2600288b16b69c135389dfe1fea89a8d)
qtbase/src/corelib/text/qstring.h (a30824a9846a67aa0d6207b4dfcbf925ce8d50e9)

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Friends

Related Symbols

Detailed Description

Member Typedef Documentation

◆ difference_type

◆ size_type

Constructor & Destructor Documentation

◆ QAnyStringView() [1/16]

◆ QAnyStringView() [2/16]

◆ QAnyStringView() [3/16]

◆ QAnyStringView() [4/16]

◆ QAnyStringView() [5/16]

◆ QAnyStringView() [6/16]

◆ QAnyStringView() [7/16]

◆ QAnyStringView() [8/16]

◆ QAnyStringView() [9/16]

◆ QAnyStringView() [10/16]

◆ QAnyStringView() [11/16]

◆ QAnyStringView() [12/16]

◆ QAnyStringView() [13/16]

◆ QAnyStringView() [14/16]

◆ QAnyStringView() [15/16]

◆ QAnyStringView() [16/16]

Member Function Documentation

◆ back()

◆ chop()

◆ chopped()

◆ compare()

◆ data()

◆ empty()

◆ equal()

◆ first()

◆ fromArray()

◆ front()

◆ isEmpty()

◆ isNull()

◆ last()

◆ left()

◆ length()

◆ mid()

◆ right()

◆ size()

◆ size_bytes()

◆ sliced() [1/2]

◆ sliced() [2/2]

◆ toString()

◆ truncate()

◆ visit() [1/2]

◆ visit() [2/2]

Friends And Related Symbol Documentation

◆ ::tst_QAnyStringView

◆ comparesEqual

◆ compareThreeWay

◆ convertToQString()

◆ operator<<

Member Data Documentation

◆ detects_US_ASCII_at_compile_time

◆ m_data

◆ m_data_utf16

◆ m_data_utf8