qbytearrayview.qdoc

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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
// Qt-Security score:insignificant reason:docs
 
/*!
    \class QByteArrayView
    \inmodule QtCore
    \brief The QByteArrayView class provides a view on an array of bytes with a read-only
           subset of the QByteArray API.
    \since 6.0
 
    \ingroup tools
    \ingroup shared
    \ingroup string-processing
 
    \reentrant
 
    \compares strong
    \compareswith strong QString QStringView QUtf8StringView QLatin1StringView \
                  QChar char16_t
    When comparing with string and Unicode character types, the content is
    interpreted as UTF-8.
    \endcompareswith
 
    A QByteArrayView references a contiguous portion of raw bytes it does
    not own. It acts as an interface type to all kinds of byte-array-like data,
    without the need to construct a QByteArray first.
 
    The byte array data may be represented as an array (or an array-compatible
    data-structure such as QByteArray, std::basic_string, etc.) of \c char,
    \c{signed char}, \c{unsigned char} or \c std::byte.
 
    QByteArrayView is designed as an interface type; its main use-case is
    as a function parameter type. When QByteArrayViews are used as automatic
    variables or data members, care must be taken to ensure that the referenced
    data (for example, owned by a QByteArray) outlives the QByteArrayView on all
    code paths, lest the byte array view ends up referencing deleted data.
 
    When used as an interface type, QByteArrayView allows a single function to accept
    a wide variety of byte-array-like data sources. One function accepting QByteArrayView
    thus replaces several function overloads (taking, for example, QByteArray, const char *,
    etc.) while at the same time enabling even more byte array data sources to be passed
    to the function.
 
    QByteArrayView should be passed by value, not by reference-to-const:
    \snippet code/src_corelib_text_qbytearrayview.cpp 0
 
    If you want to give your users maximum freedom in what type of data they
    can pass to your function, accompany the QByteArrayView overload with
    overloads for
 
    \list
        \li \e char: this overload can delegate to the QByteArrayView version:
            \snippet code/src_corelib_text_qbytearrayview.cpp 1
            even though, for technical reasons, QByteArrayView cannot provide a
            char constructor by itself.
        \li \e QByteArray: if you store an unmodified copy of the byte array and
            thus would like to take advantage of QByteArray's implicit sharing.
    \endlist
 
    QByteArrayView can also be used as the return value of a function. If you call a
    function returning QByteArrayView, take extra care to not keep the QByteArrayView
    around longer than the function promises to keep the referenced data alive.
    If in doubt, obtain a strong reference to the data by calling toByteArray() to convert
    the QByteArrayView into a QByteArray.
 
    The methods supported by QByteArrayView reflect those of \l QByteArray. In
    particular, to the limited degree that it ascribes semantics (such as
    character case, spacing, digits of numbers) to the character data viewed, it
    uses the C locale and ASCII encoding. See \l {C locale and ASCII functions}
    for details and the limitations on these methods.
 
    \section1 Compatible Byte Types
 
    QByteArrayView can be constructed on any container of bytes, where the byte type
    is one of:
 
    \list
    \li \c char (both signed and unsigned)
    \li \c std::byte
    \endlist
 
    \sa QByteArray, QStringView
*/
 
/*!
    \typedef QByteArrayView::storage_type
 
    Alias for \c char.
*/
 
/*!
    \typedef QByteArrayView::value_type
 
    Alias for \c{const char}. Provided for compatibility with the STL.
*/
 
/*!
    \typedef QByteArrayView::difference_type
 
    Alias for \c{std::ptrdiff_t}. Provided for compatibility with the STL.
*/
 
/*!
    \typedef QByteArrayView::size_type
 
    Alias for qsizetype. Provided for compatibility with the STL.
*/
 
/*!
    \typedef QByteArrayView::reference
 
    Alias for \c{value_type &}. Provided for compatibility with the STL.
 
    QByteArrayView does not support mutable references, so this is the same
    as const_reference.
*/
 
/*!
    \typedef QByteArrayView::const_reference
 
    Alias for \c{value_type &}. Provided for compatibility with the STL.
*/
 
/*!
    \typedef QByteArrayView::pointer
 
    Alias for \c{value_type *}. Provided for compatibility with the STL.
 
    QByteArrayView does not support mutable pointers, so this is the same
    as const_pointer.
*/
 
/*!
    \typedef QByteArrayView::const_pointer
 
    Alias for \c{value_type *}. Provided for compatibility with the STL.
*/
 
/*!
    \typedef QByteArrayView::iterator
 
    This typedef provides an STL-style const iterator for QByteArrayView.
 
    QByteArrayView does not support mutable iterators, so this is the same
    as const_iterator.
 
    \sa const_iterator, reverse_iterator
*/
 
/*!
    \typedef QByteArrayView::const_iterator
 
    This typedef provides an STL-style const iterator for QByteArrayView.
 
    \sa iterator, const_reverse_iterator
*/
 
/*!
    \typedef QByteArrayView::reverse_iterator
 
    This typedef provides an STL-style const reverse iterator for QByteArrayView.
 
    QByteArrayView does not support mutable reverse iterators, so this is the
    same as const_reverse_iterator.
 
    \sa const_reverse_iterator, iterator
*/
 
/*!
    \typedef QByteArrayView::const_reverse_iterator
 
    This typedef provides an STL-style const reverse iterator for QByteArrayView.
 
    \sa reverse_iterator, const_iterator
*/
 
/*!
    \fn QByteArrayView::QByteArrayView()
 
    Constructs a null byte array view.
 
    \sa isNull()
*/
 
/*!
    \fn QByteArrayView::QByteArrayView(std::nullptr_t)
 
    Constructs a null byte array view.
 
    \sa isNull()
*/
 
/*!
    \fn template <typename Byte, QByteArrayView::if_compatible_byte<Byte> = true> QByteArrayView::QByteArrayView(const Byte *data, qsizetype len)
 
    Constructs a byte array view on \a data with length \a len.
 
    The range \c{[data,len)} must remain valid for the lifetime of this QByteArrayView.
 
    Passing \nullptr as \a data is safe if \a len is 0, too, and results in a null
    byte array view.
 
    The behavior is undefined if \a len is negative or, when positive, if \a data is \nullptr.
 
    \constraints \c Byte is a compatible byte type.
 
    \sa {Compatible Byte Types}
*/
 
/*!
    \fn template <typename Byte, QByteArrayView::if_compatible_byte<Byte> = true> QByteArrayView::QByteArrayView(const Byte *first, const Byte *last)
 
    Constructs a byte array view on \a first with length (\a last - \a first).
 
    The range \c{[first,last)} must remain valid for the lifetime of
    this QByteArrayView.
 
    Passing \c \nullptr as \a first is safe if \a last is \nullptr, too,
    and results in a null byte array view.
 
    The behavior is undefined if \a last precedes \a first, or \a first
    is \nullptr and \a last is not.
 
    \constraints \c Byte is a compatible byte type.
 
    \sa {Compatible Byte Types}
*/
 
/*!
    \fn template <typename Byte> QByteArrayView::QByteArrayView(const Byte *data)
 
    Constructs a byte array view on \a data. The length is determined
    by scanning for the first \c{Byte(0)}.
 
    \a data must remain valid for the lifetime of this byte array view object.
 
    Passing \nullptr as \a data is safe and results in a null byte array view.
 
    \constraints \a data is not an array and \c Byte is a
    compatible byte type.
 
    \sa {Compatible Byte Types}
*/
 
/*!
    \fn template <typename Byte, QByteArrayView::if_compatible_byte<Byte>> QByteArrayView::QByteArrayView(const Byte (&data)[])
    \since 6.9
 
    Constructs a byte array view on \a data, an array of unknown size. The
    length is determined by scanning for the first \c{Byte(0)}.
 
    \a data must remain valid for the lifetime of this byte array view object.
 
    \constraints \c Byte is a compatible byte type.
 
    \sa {Compatible Byte Types}
*/
 
/*!
    \fn template <size_t Size> QByteArrayView::QByteArrayView(const char (&data)[Size])
 
    Constructs a byte array view on the char array \a data.
    The view covers the array until the first \c{'\0'} is encountered,
    or \c Size, whichever comes first.
    If you need the full array, use fromArray() instead.
 
    \a data must remain valid for the lifetime of this byte array view
    object.
 
    \note This constructor is only available for char array literals.
    The reasoning behind that is for compatibility with C-libraries
    which predefine "large-enough" arrays, but only use some of the
    preallocated space. To support this in an intuitive way in an
    implicit constructor overload, we need to stop at the first
    \c{char(0)}. This is logical for a char array, but not
    for a \c{std::byte} array.
    It is, however, inconsistent with the corresponding pointer (\c{Byte*}) and
    unknown-length-array (\c{Byte[]}) constructors, and so might change in a
    future version of Qt.
 
    \sa fromArray
*/
 
/*!
    \fn QByteArrayView::QByteArrayView(const QByteArray &byteArray)
 
    Constructs a byte array view on \a byteArray.
 
    \c{byteArray.data()} must remain valid for the lifetime of this byte array view object.
 
    The byte array view will be null if and only if \c{byteArray.isNull()}.
*/
 
/*!
    \fn template <typename Container, QByteArrayView::if_compatible_container<Container> = true> QByteArrayView::QByteArrayView(const Container &c)
 
    Constructs a byte array view on the array-like container \a c. The length and data
    are set via \c{std::size(c)} and \c{std::data(c)} respectively.
 
    The container's data must remain valid for the lifetime of this byte array view object.
 
    \constraints \a c is any contiguous
    container with elements of a compatible byte type.
 
    \sa {Compatible Byte Types}
*/
 
/*!
    \fn template <typename Byte, size_t Size> QByteArrayView QByteArrayView::fromArray(const Byte (&data)[Size])
 
    Constructs a byte array view on the array literal \a data. The view covers the full
    array. That includes the trailing null-terminator of \c{char} array literals.
    If you don't want the null-terminator included in the view, you can chop() it off
    when you are certain it is at the end. Alternatively you can use the constructor
    overload taking a char array literal which will create a view up to, but not including,
    the first null-terminator in the data.
 
    This function will work with any array literal of a compatible byte type.
 
    \sa {Compatible Byte Types}, QByteArrayView
*/
 
/*!
    \fn QByteArray QByteArrayView::toByteArray() const
 
    Returns a deep copy of this byte array view's data as a QByteArray.
 
    The return value will be a null QByteArray if and only if this byte array
    view is null.
*/
 
/*!
    \fn const char *QByteArrayView::data() const
 
    Returns a const \c char pointer to the first byte in the byte array view.
 
    \note The character array represented by the return value is \e not guaranteed
    to be null-terminated. The returned pointer is only safe to use for accessing
    bytes at indices that are less than this byte array view's size().
 
    \sa begin(), end()
*/
 
/*!
    \fn const char *QByteArrayView::constData() const
 
    Returns a const \c char pointer to the first byte in the byte array view.
 
    \note The character array represented by the return value is \e not guaranteed
    to be null-terminated. The returned pointer is only safe to use for accessing
    bytes at indices that are less than this byte array view's size().
 
    \sa data(), begin(), end()
*/
 
/*! //! friend
    \fn int QByteArrayView::operator==(const QByteArrayView &lhs, const QByteArrayView &rhs)
    \fn int QByteArrayView::operator!=(const QByteArrayView &lhs, const QByteArrayView &rhs)
    \fn int QByteArrayView::operator< (const QByteArrayView &lhs, const QByteArrayView &rhs)
    \fn int QByteArrayView::operator<=(const QByteArrayView &lhs, const QByteArrayView &rhs)
    \fn int QByteArrayView::operator> (const QByteArrayView &lhs, const QByteArrayView &rhs)
    \fn int QByteArrayView::operator>=(const QByteArrayView &lhs, const QByteArrayView &rhs)
 
    Comparison operators for QByteArrayView.
*/
 
/*!
    \fn int QByteArrayView::compare(QByteArrayView bv, Qt::CaseSensitivity cs = Qt::CaseSensitive) const
    \since 6.2
 
    Returns an integer less than, equal to, or greater than zero depending on
    whether this QByteArrayView sorts before, at the same position as, or after
    the QByteArrayView \a bv. The comparison is performed according to case
    sensitivity \a cs.
 
    \sa operator==()
*/
 
/*!
    \fn QByteArrayView::isValidUtf8() const
 
    Returns \c true if this byte array view contains valid UTF-8 encoded data,
    or \c false otherwise.
 
    \since 6.3
*/
 
/*!
    \fn QByteArrayView::const_iterator QByteArrayView::begin() const
 
    Returns a const \l{STL-style iterators}{STL-style iterator} pointing to the
    first byte in the byte array view.
 
    This function is provided for STL compatibility.
 
    \sa end(), cbegin(), rbegin(), data()
*/
 
/*!
    \fn QByteArrayView::const_iterator QByteArrayView::cbegin() const
 
    Same as begin().
 
    This function is provided for STL compatibility.
 
    \sa cend(), begin(), crbegin(), data()
*/
 
/*!
    \fn QByteArrayView::const_iterator QByteArrayView::end() const
 
    Returns a const \l{STL-style iterators}{STL-style iterator} pointing
    just after the last byte in the byte array view.
 
    This function is provided for STL compatibility.
 
    \sa begin(), cend(), rend()
*/
 
/*! \fn QByteArrayView::const_iterator QByteArrayView::cend() const
 
    Same as end().
 
    This function is provided for STL compatibility.
 
    \sa cbegin(), end(), crend()
*/
 
/*!
    \fn QByteArrayView::const_reverse_iterator QByteArrayView::rbegin() const
 
    Returns a const \l{STL-style iterators}{STL-style} reverse iterator pointing
    to the first byte in the byte array view, in reverse order.
 
    This function is provided for STL compatibility.
 
    \sa rend(), crbegin(), begin()
*/
 
/*!
    \fn QByteArrayView::const_reverse_iterator QByteArrayView::crbegin() const
 
    Same as rbegin().
 
    This function is provided for STL compatibility.
 
    \sa crend(), rbegin(), cbegin()
*/
 
/*!
    \fn QByteArrayView::const_reverse_iterator QByteArrayView::rend() const
 
    Returns a \l{STL-style iterators}{STL-style} reverse iterator pointing to one past
    the last byte in the byte array view, in reverse order.
 
    This function is provided for STL compatibility.
 
    \sa rbegin(), crend(), end()
*/
 
/*!
    \fn QByteArrayView::const_reverse_iterator QByteArrayView::crend() const
 
    Same as rend().
 
    This function is provided for STL compatibility.
 
    \sa crbegin(), rend(), cend()
*/
 
/*!
    \fn bool QByteArrayView::empty() const
 
    Returns \c true if this byte array view is empty - that is, \c{size() == 0}.
 
    This function is provided for STL compatibility.
 
    \sa isEmpty(), isNull(), size()
*/
 
/*!
    \fn bool QByteArrayView::isEmpty() const
 
    Returns \c true if this byte array view is empty - that is, \c{size() == 0}.
 
    \sa empty(), isNull(), size()
*/
 
/*!
    \fn bool QByteArrayView::isNull() const
 
    Returns \c true if this byte array view is null - that is, \c{data() == nullptr}.
 
    \sa empty(), isEmpty(), size()
*/
 
/*!
    \fn qsizetype QByteArrayView::size() const
 
    Returns the number of bytes in this byte array view.
 
    \sa empty(), isEmpty(), isNull()
*/
 
/*!
    \fn QByteArrayView::length() const
 
    Same as size().
 
    \sa empty(), isEmpty(), isNull(), size()
*/
 
/*!
    \fn char QByteArrayView::operator[](qsizetype n) const
 
    Returns the character at position \a n in this byte array view.
 
    The behavior is undefined if \a n is negative or not less than size().
 
    \sa at(), front(), back()
*/
 
/*!
    \fn char QByteArrayView::at(qsizetype n) const
 
    Returns the character at position \a n in this byte array view.
 
    The behavior is undefined if \a n is negative or not less than size().
 
    \sa operator[](), front(), back()
*/
 
/*!
    \fn char QByteArrayView::front() const
 
    Returns the first byte in the byte array view.
 
    This function is provided for STL compatibility.
 
    \warning Calling this function on an empty byte array view constitutes
    undefined behavior.
 
    \sa back()
*/
 
/*!
    \fn char QByteArrayView::back() const
 
    Returns the last byte in the byte array view.
 
    This function is provided for STL compatibility.
 
    \warning Calling this function on an empty byte array view constitutes
    undefined behavior.
 
    \sa front()
*/
 
/*!
    \fn QByteArrayView QByteArrayView::first(qsizetype n) const
 
    Returns a byte array view that points to the first \a n bytes
    of this byte array view. Equivalent to \c{sliced(0, n)}.
 
    \note The behavior is undefined when \a n < 0 or \a n > size().
 
    \sa last(), startsWith(), chopped(), chop(), truncate(), sliced(), slice()
*/
 
/*!
    \fn QByteArrayView QByteArrayView::last(qsizetype n) const
 
    Returns a byte array view that points to the last \a n bytes
    of this byte array view.
 
    \note The behavior is undefined when \a n < 0 or \a n > size().
 
    \sa first(), endsWith(), chopped(), chop(), truncate(), sliced(), slice()
*/
 
/*!
    \fn QByteArrayView QByteArrayView::sliced(qsizetype pos, qsizetype n) const
 
    Returns a byte array view that points to \a n bytes of this byte array
    view, starting at position \a pos.
 
//! [UB-sliced-index-length]
    \note The behavior is undefined when \a pos < 0, \a n < 0,
    or \a pos + \a n > size().
//! [UB-sliced-index-length]
 
    \sa first(), last(), chopped(), chop(), truncate(), slice()
*/
 
/*!
    \fn QByteArrayView QByteArrayView::sliced(qsizetype pos) const
 
    Returns a byte array view starting at position \a pos in this object,
    and extending to its end.
 
//! [UB-sliced-index-only]
    \note The behavior is undefined when \a pos < 0 or \a pos > size().
//! [UB-sliced-index-only]
 
    \sa first(), last(), chopped(), chop(), truncate(), slice()
*/
 
/*!
    \fn QByteArrayView &QByteArrayView::slice(qsizetype pos, qsizetype n)
    \since 6.8
 
    Modifies this byte array view to start at position \a pos, extending for
    \a n bytes.
 
    \include qbytearrayview.qdoc UB-sliced-index-length
 
    \sa sliced(), first(), last(), chopped(), chop(), truncate()
*/
 
/*!
    \fn QByteArrayView &QByteArrayView::slice(qsizetype pos)
    \since 6.8
    \overload
 
    Modifies this byte array view to start at position \a pos, extending
    to its end.
 
    \include qbytearrayview.qdoc UB-sliced-index-only
 
    \sa sliced(), first(), last(), chopped(), chop(), truncate()
*/
 
/*!
    \fn QByteArrayView QByteArrayView::chopped(qsizetype length) const
 
    Returns a copy of this byte array view that omits its last \a length bytes.
    In other words, returns a byte array view of length size() - \a length starting
    at the beginning of this object.
 
    Same as \c{first(size() - length)}.
 
    \note The behavior is undefined when \a length < 0 or \a length > size().
 
    \sa first(), last(), sliced(), chop(), truncate(), slice()
*/
 
/*!
    \fn void QByteArrayView::truncate(qsizetype length)
 
    Truncates this byte array view to length \a length.
 
    Same as \c{*this = first(length)}.
 
    \note The behavior is undefined when \a length < 0 or \a length > size().
 
    \sa first(), last(), sliced(), chopped(), chop()
*/
 
/*!
    \fn void QByteArrayView::chop(qsizetype length)
 
    Truncates this byte array view by \a length characters.
 
    Same as \c{*this = first(size() - length)}.
 
    \note The behavior is undefined when \a length < 0 or \a length > size().
 
    \sa sliced(), first(), last(), chopped(), truncate(), slice()
*/
 
/*!
    \fn QByteArrayView QByteArrayView::mid(qsizetype start, qsizetype length) const
    \since 6.5
 
    \deprecated Use sliced() instead in new code.
 
    Returns the subarray of length \a length starting at position
    \a start in this object.
 
    Returns an empty byte array view if \a start exceeds the
    length of the byte array view. If there are less than \a length characters
    available in the byte array view starting at \a start, or if
    \a length is negative (default), the function returns all characters that
    are available from \a start.
 
    \sa first(), last(), sliced(), chopped(), chop(), truncate(), slice()
*/
 
/*!
    \fn QByteArrayView QByteArrayView::left(qsizetype length) const
    \since 6.5
 
    \deprecated Use first() instead in new code.
 
    Returns the subarray of length \a length starting at position
    0 in this object.
 
    The entire byte array view is returned if \a length is greater than or equal
    to size(), or less than zero.
 
    \sa first(), last(), sliced(), startsWith(), chopped(), chop(), truncate(), slice()
*/
 
/*!
    \fn QByteArrayView QByteArrayView::right(qsizetype length) const
    \since 6.5
 
    \deprecated Use last() instead in new code.
 
    Returns the subarray of length \a length starting at position
    size() - \a length in this object.
 
    The entire byte array view is returned if \a length is greater than or equal
    to size(), or less than zero.
 
    \sa first(), last(), sliced(), endsWith(), chopped(), chop(), truncate(), slice()
*/
 
/*!
    \fn QByteArrayView QByteArrayView::trimmed() const noexcept
    \since 6.3
 
    Returns a copy of this byte array view with spacing characters
    removed from the start and end.
 
    The spacing characters are those for which the standard C++ \c isspace()
    function returns \c true in the C locale; these are the ASCII characters
    tabulation '\\t', line feed '\\n', carriage return '\\r', vertical
    tabulation '\\v', form feed '\\f', and space ' '.
 
    \sa QChar::SpecialCharacter, {QByteArray#Spacing Characters}{Spacing Characters}
*/
 
/*!
    \fn qlonglong QByteArrayView::toLongLong(bool *ok, int base) const
    \since 6.3
 
    Returns this byte array view converted to a \c {long long} using base \a
    base, which is ten by default. Bases 0 and 2 through 36 are supported, using
    letters for digits beyond 9; A is ten, B is eleven and so on.
 
    If \a base is 0, the base is determined automatically using the following
    rules: if the byte array view begins with "0x", the rest of it is read as
    hexadecimal (base 16); otherwise, if it begins with "0", the rest of it is
    read as octal (base 8); otherwise it is read as decimal.
 
    Returns 0 if the conversion fails.
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
*/
 
/*!
    \fn qulonglong QByteArrayView::toULongLong(bool *ok, int base) const
    \since 6.3
 
    Returns this byte array view converted to an \c {unsigned long long} using
    base \a base, which is ten by default. Bases 0 and 2 through 36 are
    supported, using letters for digits beyond 9; A is ten, B is eleven and so
    on.
 
    If \a base is 0, the base is determined automatically using the following
    rules: if the byte array view begins with "0x", the rest of it is read as
    hexadecimal (base 16); otherwise, if it begins with "0", the rest of it is
    read as octal (base 8); otherwise it is read as decimal.
 
    Returns 0 if the conversion fails.
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
*/
 
/*!
    \fn int QByteArrayView::toInt(bool *ok, int base) const
    \since 6.3
 
    Returns this byte array view converted to an \c int using base \a base,
    which is ten by default. Bases 0 and 2 through 36 are supported, using
    letters for digits beyond 9; A is ten, B is eleven and so on.
 
    If \a base is 0, the base is determined automatically using the following
    rules: if the byte array view begins with "0x", the rest of it is read as
    hexadecimal (base 16); otherwise, if it begins with "0", the rest of it is
    read as octal (base 8); otherwise it is read as decimal.
 
    Returns 0 if the conversion fails.
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \snippet code/src_corelib_text_qbytearrayview.cpp 2
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
*/
 
/*!
    \fn uint QByteArrayView::toUInt(bool *ok, int base) const
    \since 6.3
 
    Returns this byte array view converted to an \c {unsigned int} using base \a
    base, which is ten by default. Bases 0 and 2 through 36 are supported, using
    letters for digits beyond 9; A is ten, B is eleven and so on.
 
    If \a base is 0, the base is determined automatically using the following
    rules: if the byte array view begins with "0x", the rest of it is read as
    hexadecimal (base 16); otherwise, if it begins with "0", the rest of it is
    read as octal (base 8); otherwise it is read as decimal.
 
    Returns 0 if the conversion fails.
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
*/
 
/*!
    \fn long QByteArrayView::toLong(bool *ok, int base) const
    \since 6.3
 
    Returns this byte array view converted to a \c long int using base \a base,
    which is ten by default. Bases 0 and 2 through 36 are supported, using
    letters for digits beyond 9; A is ten, B is eleven and so on.
 
    If \a base is 0, the base is determined automatically using the following
    rules: if the byte array view begins with "0x", the rest of it is read as
    hexadecimal (base 16); otherwise, if it begins with "0", the rest of it is
    read as octal (base 8); otherwise it is read as decimal.
 
    Returns 0 if the conversion fails.
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \snippet code/src_corelib_text_qbytearrayview.cpp 3
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
*/
 
/*!
    \fn ulong QByteArrayView::toULong(bool *ok, int base) const
    \since 6.3
 
    Returns this byte array view converted to an \c {unsigned long int} using
    base \a base, which is ten by default. Bases 0 and 2 through 36 are
    supported, using letters for digits beyond 9; A is ten, B is eleven and so
    on.
 
    If \a base is 0, the base is determined automatically using the following
    rules: if the byte array view begins with "0x", the rest of it is read as
    hexadecimal (base 16); otherwise, if it begins with "0", the rest of it is
    read as octal (base 8); otherwise it is read as decimal.
 
    Returns 0 if the conversion fails.
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
*/
 
/*!
    \fn short QByteArrayView::toShort(bool *ok, int base) const
    \since 6.3
 
    Returns this byte array view converted to a \c short using base \a base,
    which is ten by default. Bases 0 and 2 through 36 are supported, using
    letters for digits beyond 9; A is ten, B is eleven and so on.
 
    If \a base is 0, the base is determined automatically using the following
    rules: if the byte array view begins with "0x", the rest of it is read as
    hexadecimal (base 16); otherwise, if it begins with "0", the rest of it is
    read as octal (base 8); otherwise it is read as decimal.
 
    Returns 0 if the conversion fails.
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
*/
 
/*!
    \fn ushort QByteArrayView::toUShort(bool *ok, int base) const
    \since 6.3
 
    Returns this byte array view converted to an \c {unsigned short} using base
    \a base, which is ten by default. Bases 0 and 2 through 36 are supported,
    using letters for digits beyond 9; A is ten, B is eleven and so on.
 
    If \a base is 0, the base is determined automatically using the following
    rules: if the byte array view begins with "0x", the rest of it is read as
    hexadecimal (base 16); otherwise, if it begins with "0", the rest of it is
    read as octal (base 8); otherwise it is read as decimal.
 
    Returns 0 if the conversion fails.
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
*/
 
/*!
    \fn double QByteArrayView::toDouble(bool *ok) const
    \since 6.3
 
    Returns this byte array view converted to a \c double value.
 
    Returns an infinity if the conversion overflows or 0.0 if the
    conversion fails for other reasons (e.g. underflow).
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \warning The QByteArrayView content may only contain valid numerical
    characters which includes the plus/minus sign, the character e used in
    scientific notation, and the decimal point. Including the unit or additional
    characters leads to a conversion error.
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
 
    This function ignores leading and trailing spacing characters.
*/
 
/*!
    \fn float QByteArrayView::toFloat(bool *ok) const
    \since 6.3
 
    Returns this byte array view converted to a \c float value.
 
    Returns an infinity if the conversion overflows or 0.0 if the
    conversion fails for other reasons (e.g. underflow).
 
    If \a ok is not \nullptr, failure is reported by setting *\a{ok}
    to \c false, and success by setting *\a{ok} to \c true.
 
    \snippet code/src_corelib_text_qbytearrayview.cpp 4
 
    \warning The QByteArrayView content may only contain valid numerical
    characters which includes the plus/minus sign, the character e used in
    scientific notation, and the decimal point. Including the unit or additional
    characters leads to a conversion error.
 
    \note The conversion of the number is performed in the default C locale,
    regardless of the user's locale. Use QLocale to perform locale-aware
    conversions between numbers and strings.
 
    This function ignores leading and trailing whitespace.
*/
 
/*!
    \fn bool QByteArrayView::startsWith(QByteArrayView bv) const
    \fn bool QByteArrayView::startsWith(char ch) const
 
    Returns \c true if this byte array view starts with byte array view \a bv
    or character \a ch, respectively; otherwise returns \c false.
 
    \sa endsWith()
*/
 
/*!
    \fn bool QByteArrayView::endsWith(QByteArrayView bv) const
    \fn bool QByteArrayView::endsWith(char ch) const
 
    Returns \c true if this byte array view ends with byte array view \a bv
    or character \a ch, respectively; otherwise returns \c false.
 
    \sa startsWith()
*/
 
/*!
    \fn qsizetype QByteArrayView::indexOf(QByteArrayView bv, qsizetype from = 0) const
    \fn qsizetype QByteArrayView::indexOf(char ch, qsizetype from = 0) const
 
    Returns the index position of either the start of the first occurrence of
    the sequence of bytes viewed by \a bv or the first occurrence of byte \a ch,
    respectively, in this byte array view, searching forward from index position
    \a from.Returns -1 if no match is found.
 
    \include qstring.qdocinc negative-index-start-search-from-end
 
    \sa lastIndexOf(), contains()
*/
 
/*!
    \fn bool QByteArrayView::contains(QByteArrayView bv) const
    \fn bool QByteArrayView::contains(char ch) const
 
    Returns \c true if this byte array view contains an occurrence of the sequence
    of bytes viewed by \a bv or character \a ch, respectively; otherwise returns
    \c false.
 
    \sa indexOf(), lastIndexOf()
*/
 
/*!
    \fn qsizetype QByteArrayView::lastIndexOf(QByteArrayView bv, qsizetype from) const
    \fn qsizetype QByteArrayView::lastIndexOf(char ch, qsizetype from = -1) const
 
    Returns the index position of either the start of the last occurrence of
    the sequence of bytes viewed by \a bv or the last occurrence of byte \a ch,
    respectively, in this byte array view, searching backward from index position
    \a from.
 
    \include qstring.qdocinc negative-index-start-search-from-end
 
    Returns -1 if no match is found.
 
    \note When searching for a 0-length \a bv, the match at the end of
    the data is excluded from the search by a negative \a from, even
    though \c{-1} is normally thought of as searching from the end of
    the view: the match at the end is \e after the last character, so
    it is excluded. To include such a final empty match, either give a
    positive value for \a from or omit the \a from parameter entirely.
 
    \sa indexOf(), contains()
*/
 
/*!
    \fn qsizetype QByteArrayView::lastIndexOf(QByteArrayView bv) const
    \since 6.2
    \overload
 
    Returns the index position of the start of the last
    occurrence of the sequence of bytes viewed by \a bv in this byte
    array view, searching backward from the end of this byte array
    view. Returns -1 if no match is found.
 
    \sa indexOf(), contains()
*/
 
/*!
    \fn qsizetype QByteArrayView::count(QByteArrayView bv) const
 
    Returns the number of (potentially overlapping) occurrences of the
    sequence of bytes viewed by \a bv in this byte array view.
 
    \sa contains(), indexOf()
*/
 
/*!
    \fn bool QByteArrayView::count(char ch) const
    \overload
 
    Returns the number of occurrences of byte \a ch in this byte array view.
 
    \sa contains(), indexOf()
*/
 
/*!
    \fn QByteArrayView qToByteArrayViewIgnoringNull(const QByteArray &b);
    \internal
 
    Convert \a b to a QByteArrayView ignoring \c{b.isNull()}.
 
    Returns a byte array view that references \a{b}'s data, but is never null.
 
    This is a faster way to convert a QByteArray to a QByteArrayView,
    if null QByteArray can legitimately be treated as empty ones.
 
    \sa QByteArray::isNull(), QByteArrayView
*/
 
/*!
    \fn QByteArrayView::operator std::string_view() const
    \since 6.7
 
    Converts this QByteArrayView object to a \c{std::string_view} object.
    The returned view will have the same data pointer and length of
    this view.
*/
 
/*!
    \fn QByteArrayView::maxSize()
    \since 6.8
 
    It returns the maximum number of elements that the view can
    theoretically represent. In practice, the number can be much smaller,
    limited by the amount of memory available to the system.
*/
 
/*!
    \fn QByteArrayView::max_size() const
    \since 6.8
 
    This function is provided for STL compatibility.
 
    Returns maxSize().
*/