corelib/text/qcollator.cpp

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** Copyright (C) 2013 Aleix Pol Gonzalez <aleixpol@kde.org>
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#include "qcollator_p.h"
#include "qstringlist.h"
#include "qstring.h"

#include "qdebug.h"

QT_BEGIN_NAMESPACE

/*!
    \class QCollator
    \inmodule QtCore
    \brief The QCollator class compares strings according to a localized collation algorithm.

    \since 5.2

    \reentrant
    \ingroup i18n
    \ingroup string-processing
    \ingroup shared

    QCollator is initialized with a QLocale and an optional collation strategy.
    It tries to initialize the collator with the specified values. The collator
    can then be used to compare and sort strings in a locale dependent fashion.

    A QCollator object can be used together with template based sorting
    algorithms such as std::sort to sort a list of QStrings.

    In addition to the locale and collation strategy, several optional flags can
    be set that influence the result of the collation.
*/

/*!
  \since 5.13

  Constructs a QCollator using the system's default collation locale.

  \sa setLocale(), QLocale::collation()
*/
QCollator::QCollator()
    : d(new QCollatorPrivate(QLocale::system().collation()))
{
    d->init();
}

/*!
    Constructs a QCollator from \a locale.

    \sa setLocale()
 */
QCollator::QCollator(const QLocale &locale)
    : d(new QCollatorPrivate(locale))
{
}

/*!
    Creates a copy of \a other.
 */
QCollator::QCollator(const QCollator &other)
    : d(other.d)
{
    if (d) {
        // Ensure clean, lest both copies try to init() at the same time:
        if (d->dirty)
            d->init();
        d->ref.ref();
    }
}

/*!
    Destroys the collator.
 */
QCollator::~QCollator()
{
    if (d && !d->ref.deref())
        delete d;
}

/*!
    Assigns \a other to this collator.
 */
QCollator &QCollator::operator=(const QCollator &other)
{
    if (this != &other) {
        if (d && !d->ref.deref())
            delete d;
        d = other.d;
        if (d) {
            // Ensure clean, lest both copies try to init() at the same time:
            if (d->dirty)
                d->init();
            d->ref.ref();
        }
    }
    return *this;
}

/*!
    \fn QCollator::QCollator(QCollator &&other)

    Move constructor. Moves from \a other into this collator.

    Note that a moved-from QCollator can only be destroyed or assigned to.
    The effect of calling other functions than the destructor or one of the
    assignment operators is undefined.
*/

/*!
    \fn QCollator & QCollator::operator=(QCollator && other)

    Move-assigns from \a other to this collator.

    Note that a moved-from QCollator can only be destroyed or assigned to.
    The effect of calling other functions than the destructor or one of the
    assignment operators is undefined.
*/

/*!
    \fn void QCollator::swap(QCollator &other)

    Swaps this collator with \a other. This function is very fast and
    never fails.
*/

/*!
    \internal
 */
void QCollator::detach()
{
    if (d->ref.loadRelaxed() != 1) {
        QCollatorPrivate *x = new QCollatorPrivate(d->locale);
        if (!d->ref.deref())
            delete d;
        d = x;
    }
    // All callers need this, because about to modify the object:
    d->dirty = true;
}

/*!
    Sets the locale of the collator to \a locale.
 */
void QCollator::setLocale(const QLocale &locale)
{
    if (locale == d->locale)
        return;

    detach();
    d->locale = locale;
}

/*!
    Returns the locale of the collator.
 */
QLocale QCollator::locale() const
{
    return d->locale;
}

/*!
    \fn void QCollator::setCaseSensitivity(Qt::CaseSensitivity sensitivity)

    Sets the case \a sensitivity of the collator.

    \sa caseSensitivity()
 */
void QCollator::setCaseSensitivity(Qt::CaseSensitivity cs)
{
    if (d->caseSensitivity == cs)
        return;

    detach();
    d->caseSensitivity = cs;
}

/*!
    \fn Qt::CaseSensitivity QCollator::caseSensitivity() const

    Returns case sensitivity of the collator.

    \sa setCaseSensitivity()
 */
Qt::CaseSensitivity QCollator::caseSensitivity() const
{
    return d->caseSensitivity;
}

/*!
    \fn void QCollator::setNumericMode(bool on)

    Enables numeric sorting mode when \a on is set to true.

    This will enable proper sorting of numeric digits, so that e.g. 100 sorts
    after 99.

    By default this mode is off.

    \sa numericMode()
 */
void QCollator::setNumericMode(bool on)
{
    if (d->numericMode == on)
        return;

    detach();
    d->numericMode = on;
}

/*!
    \fn bool QCollator::numericMode() const

    Returns \c true if numeric sorting is enabled, false otherwise.

    \sa setNumericMode()
 */
bool QCollator::numericMode() const
{
    return d->numericMode;
}

/*!
    \fn void QCollator::setIgnorePunctuation(bool on)

    If \a on is set to true, punctuation characters and symbols are ignored when
    determining sort order.

    The default is locale dependent.

    \note This method is not currently supported if Qt is configured to not use
    ICU on Linux.

    \sa ignorePunctuation()
 */
void QCollator::setIgnorePunctuation(bool on)
{
    if (d->ignorePunctuation == on)
        return;

    detach();
    d->ignorePunctuation = on;
}

/*!
    \fn bool QCollator::ignorePunctuation() const

    Returns \c true if punctuation characters and symbols are ignored when
    determining sort order.

    \sa setIgnorePunctuation()
 */
bool QCollator::ignorePunctuation() const
{
    return d->ignorePunctuation;
}

/*!
    \since 5.13
    \fn bool QCollator::operator()(QStringView s1, QStringView s2) const
    \internal
*/

/*!
    \since 5.13
    \fn int QCollator::compare(QStringView s1, QStringView s2) const

    Compares \a s1 with \a s2.

    Returns an integer less than, equal to, or greater than zero depending on
    whether \a s1 sorts before, with or after \a s2.
*/
#if QT_STRINGVIEW_LEVEL < 2
/*!
    \fn bool QCollator::operator()(const QString &s1, const QString &s2) const
    \internal
*/

/*!
    \overload

    Compares \a s1 with \a s2.

    Returns an integer less than, equal to, or greater than zero depending on
    whether \a s1 sorts before, with or after \a s2.
*/
int QCollator::compare(const QString &s1, const QString &s2) const
{
    return compare(QStringView(s1), QStringView(s2));
}

/*!
    \overload

    Compares \a s1 with \a s2.

    Returns an integer less than, equal to, or greater than zero depending on
    whether \a s1 sorts before, with or after \a s2.
 */
int QCollator::compare(const QStringRef &s1, const QStringRef &s2) const
{
    return compare(QStringView(s1), QStringView(s2));
}

/*!
    \overload

    Compares \a s1 with \a s2. \a len1 and \a len2 specify the lengths of the
    QChar arrays pointed to by \a s1 and \a s2.

    Returns an integer less than, equal to, or greater than zero depending on
    whether \a s1 sorts before, with or after \a s2.
*/
int QCollator::compare(const QChar *s1, int len1, const QChar *s2, int len2) const
{
    return compare(QStringView(s1, len1), QStringView(s2, len2));
}
#endif // QT_STRINGVIEW_LEVEL < 2

/*!
    \fn QCollatorSortKey QCollator::sortKey(const QString &string) const

    Returns a sortKey for \a string.

    Creating the sort key is usually somewhat slower, than using the compare()
    methods directly. But if the string is compared repeatedly (e.g. when
    sorting a whole list of strings), it's usually faster to create the sort
    keys for each string and then sort using the keys.

    \note Not supported with the C (a.k.a. POSIX) locale on Darwin.
 */

/*!
    \class QCollatorSortKey
    \inmodule QtCore
    \brief The QCollatorSortKey class can be used to speed up string collation.

    \since 5.2

    The QCollatorSortKey class is always created by QCollator::sortKey() and is
    used for fast strings collation, for example when collating many strings.

    \reentrant
    \ingroup i18n
    \ingroup string-processing
    \ingroup shared

    \sa QCollator, QCollator::sortKey()
*/

/*!
    \internal
 */
QCollatorSortKey::QCollatorSortKey(QCollatorSortKeyPrivate *d)
    : d(d)
{
}

/*!
    Constructs a copy of the \a other collator key.
*/
QCollatorSortKey::QCollatorSortKey(const QCollatorSortKey &other)
    : d(other.d)
{
}

/*!
    Destroys the collator key.
 */
QCollatorSortKey::~QCollatorSortKey()
{
}

/*!
    Assigns \a other to this collator key.
 */
QCollatorSortKey& QCollatorSortKey::operator=(const QCollatorSortKey &other)
{
    if (this != &other) {
        d = other.d;
    }
    return *this;
}

/*!
    \fn QCollatorSortKey &QCollatorSortKey::operator=(QCollatorSortKey && other)

    Move-assigns \a other to this collator key.
*/

/*!
    \fn bool operator<(const QCollatorSortKey &lhs, const QCollatorSortKey &rhs)
    \relates QCollatorSortKey

    According to the QCollator that created the keys, returns \c true if \a lhs
    should be sorted before \a rhs; otherwise returns \c false.

    \sa QCollatorSortKey::compare()
 */

/*!
    \fn void QCollatorSortKey::swap(QCollatorSortKey & other)

    Swaps this collator key with \a other.
*/

/*!
    \fn int QCollatorSortKey::compare(const QCollatorSortKey &otherKey) const

    Compares this key to \a otherKey.

    Returns a negative value if the key is less than \a otherKey, 0 if the key
    is equal to \a otherKey or a positive value if the key is greater than \a
    otherKey.

    \sa operator<()
 */

QT_END_NAMESPACE