| /**************************************************************************** |
| ** |
| ** Copyright (C) 2015 The Qt Company Ltd. |
| ** Copyright (C) 2014 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Giuseppe D'Angelo <giuseppe.dangelo@kdab.com> |
| ** Contact: http://www.qt.io/licensing/ |
| ** |
| ** This file is part of the QtCore module of the Qt Toolkit. |
| ** |
| ** $QT_BEGIN_LICENSE:LGPL21$ |
| ** Commercial License Usage |
| ** Licensees holding valid commercial Qt licenses may use this file in |
| ** accordance with the commercial license agreement provided with the |
| ** Software or, alternatively, in accordance with the terms contained in |
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| ** and conditions see http://www.qt.io/terms-conditions. For further |
| ** information use the contact form at http://www.qt.io/contact-us. |
| ** |
| ** GNU Lesser General Public License Usage |
| ** Alternatively, this file may be used under the terms of the GNU Lesser |
| ** General Public License version 2.1 or version 3 as published by the Free |
| ** Software Foundation and appearing in the file LICENSE.LGPLv21 and |
| ** LICENSE.LGPLv3 included in the packaging of this file. Please review the |
| ** following information to ensure the GNU Lesser General Public License |
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| ** |
| ** As a special exception, The Qt Company gives you certain additional |
| ** rights. These rights are described in The Qt Company LGPL Exception |
| ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. |
| ** |
| ** $QT_END_LICENSE$ |
| ** |
| ****************************************************************************/ |
| |
| #ifndef QSTRINGITERATOR_H |
| #define QSTRINGITERATOR_H |
| |
| // |
| // W A R N I N G |
| // ------------- |
| // |
| // This file is not part of the Qt API. It exists purely as an |
| // implementation detail. This header file may change from version to |
| // version without notice, or even be removed. |
| // |
| // We mean it. |
| // |
| |
| #include <QtCore/qstring.h> |
| |
| QT_BEGIN_NAMESPACE |
| |
| class QStringIterator |
| { |
| QString::const_iterator i, pos, e; |
| |
| public: |
| inline explicit QStringIterator(const QString &string) |
| : i(string.constBegin()), |
| pos(string.constBegin()), |
| e(string.constEnd()) |
| { |
| } |
| |
| inline explicit QStringIterator(const QChar *begin, const QChar *end) |
| : i(begin), |
| pos(begin), |
| e(end) |
| { |
| } |
| |
| inline QString::const_iterator position() const |
| { |
| return pos; |
| } |
| |
| inline int index() const |
| { |
| return pos - i; |
| } |
| |
| inline void setPosition(QString::const_iterator position) |
| { |
| Q_ASSERT_X(i <= position && position <= e, Q_FUNC_INFO, "position out of bounds"); |
| pos = position; |
| } |
| |
| // forward iteration |
| |
| inline bool hasNext() const |
| { |
| return pos < e; |
| } |
| |
| inline void advance() |
| { |
| Q_ASSERT_X(hasNext(), Q_FUNC_INFO, "iterator hasn't a next item"); |
| |
| if (Q_UNLIKELY((pos++)->isHighSurrogate())) { |
| if (Q_LIKELY(pos != e && pos->isLowSurrogate())) |
| ++pos; |
| } |
| } |
| |
| inline void advanceUnchecked() |
| { |
| Q_ASSERT_X(hasNext(), Q_FUNC_INFO, "iterator hasn't a next item"); |
| |
| if (Q_UNLIKELY((pos++)->isHighSurrogate())) |
| ++pos; |
| } |
| |
| inline uint peekNextUnchecked() const |
| { |
| Q_ASSERT_X(hasNext(), Q_FUNC_INFO, "iterator hasn't a next item"); |
| |
| if (Q_UNLIKELY(pos->isHighSurrogate())) |
| return QChar::surrogateToUcs4(pos[0], pos[1]); |
| |
| return pos->unicode(); |
| } |
| |
| inline uint peekNext(uint invalidAs = QChar::ReplacementCharacter) const |
| { |
| Q_ASSERT_X(hasNext(), Q_FUNC_INFO, "iterator hasn't a next item"); |
| |
| if (Q_UNLIKELY(pos->isSurrogate())) { |
| if (Q_LIKELY(pos->isHighSurrogate())) { |
| const QChar *low = pos + 1; |
| if (Q_LIKELY(low != e && low->isLowSurrogate())) |
| return QChar::surrogateToUcs4(*pos, *low); |
| } |
| return invalidAs; |
| } |
| |
| return pos->unicode(); |
| } |
| |
| inline uint nextUnchecked() |
| { |
| Q_ASSERT_X(hasNext(), Q_FUNC_INFO, "iterator hasn't a next item"); |
| |
| const QChar cur = *pos++; |
| if (Q_UNLIKELY(cur.isHighSurrogate())) |
| return QChar::surrogateToUcs4(cur, *pos++); |
| return cur.unicode(); |
| } |
| |
| inline uint next(uint invalidAs = QChar::ReplacementCharacter) |
| { |
| Q_ASSERT_X(hasNext(), Q_FUNC_INFO, "iterator hasn't a next item"); |
| |
| const QChar uc = *pos++; |
| if (Q_UNLIKELY(uc.isSurrogate())) { |
| if (Q_LIKELY(uc.isHighSurrogate() && pos < e && pos->isLowSurrogate())) |
| return QChar::surrogateToUcs4(uc, *pos++); |
| return invalidAs; |
| } |
| |
| return uc.unicode(); |
| } |
| |
| // backwards iteration |
| |
| inline bool hasPrevious() const |
| { |
| return pos > i; |
| } |
| |
| inline void recede() |
| { |
| Q_ASSERT_X(hasPrevious(), Q_FUNC_INFO, "iterator hasn't a previous item"); |
| |
| if (Q_UNLIKELY((--pos)->isLowSurrogate())) { |
| const QChar *high = pos - 1; |
| if (Q_LIKELY(high != i - 1 && high->isHighSurrogate())) |
| --pos; |
| } |
| } |
| |
| inline void recedeUnchecked() |
| { |
| Q_ASSERT_X(hasPrevious(), Q_FUNC_INFO, "iterator hasn't a previous item"); |
| |
| if (Q_UNLIKELY((--pos)->isLowSurrogate())) |
| --pos; |
| } |
| |
| inline uint peekPreviousUnchecked() const |
| { |
| Q_ASSERT_X(hasPrevious(), Q_FUNC_INFO, "iterator hasn't a previous item"); |
| |
| if (Q_UNLIKELY(pos[-1].isLowSurrogate())) |
| return QChar::surrogateToUcs4(pos[-2], pos[-1]); |
| return pos[-1].unicode(); |
| } |
| |
| inline uint peekPrevious(uint invalidAs = QChar::ReplacementCharacter) const |
| { |
| Q_ASSERT_X(hasPrevious(), Q_FUNC_INFO, "iterator hasn't a previous item"); |
| |
| if (Q_UNLIKELY(pos[-1].isSurrogate())) { |
| if (Q_LIKELY(pos[-1].isLowSurrogate())) { |
| const QChar *high = pos - 2; |
| if (Q_LIKELY(high != i - 1 && high->isHighSurrogate())) |
| return QChar::surrogateToUcs4(*high, pos[-1]); |
| } |
| return invalidAs; |
| } |
| |
| return pos[-1].unicode(); |
| } |
| |
| inline uint previousUnchecked() |
| { |
| Q_ASSERT_X(hasPrevious(), Q_FUNC_INFO, "iterator hasn't a previous item"); |
| |
| const QChar cur = *--pos; |
| if (Q_UNLIKELY(cur.isLowSurrogate())) |
| return QChar::surrogateToUcs4(*--pos, cur); |
| return cur.unicode(); |
| } |
| |
| inline uint previous(uint invalidAs = QChar::ReplacementCharacter) |
| { |
| Q_ASSERT_X(hasPrevious(), Q_FUNC_INFO, "iterator hasn't a previous item"); |
| |
| const QChar uc = *--pos; |
| if (Q_UNLIKELY(uc.isSurrogate())) { |
| if (Q_LIKELY(uc.isLowSurrogate() && pos > i && pos[-1].isHighSurrogate())) |
| return QChar::surrogateToUcs4(*--pos, uc); |
| return invalidAs; |
| } |
| |
| return uc.unicode(); |
| } |
| }; |
| |
| QT_END_NAMESPACE |
| |
| #endif // QSTRINGITERATOR_H |
