1 /**************************************************************************** 2 ** 3 ** Copyright (C) 2017 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Marc Mutz <marc.mutz@kdab.com> 4 ** Copyright (C) 2019 Mail.ru Group. 5 ** Contact: http://www.qt.io/licensing/ 6 ** 7 ** This file is part of the QtCore module of the Qt Toolkit. 8 ** 9 ** $QT_BEGIN_LICENSE:LGPL$ 10 ** Commercial License Usage 11 ** Licensees holding valid commercial Qt licenses may use this file in 12 ** accordance with the commercial license agreement provided with the 13 ** Software or, alternatively, in accordance with the terms contained in 14 ** a written agreement between you and The Qt Company. For licensing terms 15 ** and conditions see https://www.qt.io/terms-conditions. For further 16 ** information use the contact form at https://www.qt.io/contact-us. 17 ** 18 ** GNU Lesser General Public License Usage 19 ** Alternatively, this file may be used under the terms of the GNU Lesser 20 ** General Public License version 3 as published by the Free Software 21 ** Foundation and appearing in the file LICENSE.LGPL3 included in the 22 ** packaging of this file. Please review the following information to 23 ** ensure the GNU Lesser General Public License version 3 requirements 24 ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. 25 ** 26 ** GNU General Public License Usage 27 ** Alternatively, this file may be used under the terms of the GNU 28 ** General Public License version 2.0 or (at your option) the GNU General 29 ** Public license version 3 or any later version approved by the KDE Free 30 ** Qt Foundation. The licenses are as published by the Free Software 31 ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 32 ** included in the packaging of this file. Please review the following 33 ** information to ensure the GNU General Public License requirements will 34 ** be met: https://www.gnu.org/licenses/gpl-2.0.html and 35 ** https://www.gnu.org/licenses/gpl-3.0.html. 36 ** 37 ** $QT_END_LICENSE$ 38 ** 39 ****************************************************************************/ 40 #ifndef QSTRINGVIEW_H 41 #define QSTRINGVIEW_H 42 43 #ifndef QT_STRINGVIEW_LEVEL 44 # define QT_STRINGVIEW_LEVEL 1 45 #endif 46 47 #include <QtCore/qchar.h> 48 #include <QtCore/qbytearray.h> 49 #include <QtCore/qstringliteral.h> 50 #include <QtCore/qstringalgorithms.h> 51 52 #include <string> 53 54 QT_BEGIN_NAMESPACE 55 56 class QString; 57 class QStringRef; 58 class QRegularExpression; 59 60 namespace QtPrivate { 61 template <typename Char> 62 struct IsCompatibleCharTypeHelper 63 : std::integral_constant<bool, 64 std::is_same<Char, QChar>::value || 65 std::is_same<Char, ushort>::value || 66 std::is_same<Char, char16_t>::value || 67 (std::is_same<Char, wchar_t>::value && sizeof(wchar_t) == sizeof(QChar))> {}; 68 template <typename Char> 69 struct IsCompatibleCharType 70 : IsCompatibleCharTypeHelper<typename std::remove_cv<typename std::remove_reference<Char>::type>::type> {}; 71 72 template <typename Array> 73 struct IsCompatibleArrayHelper : std::false_type {}; 74 template <typename Char, size_t N> 75 struct IsCompatibleArrayHelper<Char[N]> 76 : IsCompatibleCharType<Char> {}; 77 template <typename Array> 78 struct IsCompatibleArray 79 : IsCompatibleArrayHelper<typename std::remove_cv<typename std::remove_reference<Array>::type>::type> {}; 80 81 template <typename Pointer> 82 struct IsCompatiblePointerHelper : std::false_type {}; 83 template <typename Char> 84 struct IsCompatiblePointerHelper<Char*> 85 : IsCompatibleCharType<Char> {}; 86 template <typename Pointer> 87 struct IsCompatiblePointer 88 : IsCompatiblePointerHelper<typename std::remove_cv<typename std::remove_reference<Pointer>::type>::type> {}; 89 90 template <typename T> 91 struct IsCompatibleStdBasicStringHelper : std::false_type {}; 92 template <typename Char, typename...Args> 93 struct IsCompatibleStdBasicStringHelper<std::basic_string<Char, Args...> > 94 : IsCompatibleCharType<Char> {}; 95 96 template <typename T> 97 struct IsCompatibleStdBasicString 98 : IsCompatibleStdBasicStringHelper< 99 typename std::remove_cv<typename std::remove_reference<T>::type>::type 100 > {}; 101 102 } // namespace QtPrivate 103 104 class QStringView 105 { 106 public: 107 typedef char16_t storage_type; 108 typedef const QChar value_type; 109 typedef std::ptrdiff_t difference_type; 110 typedef qsizetype size_type; 111 typedef value_type &reference; 112 typedef value_type &const_reference; 113 typedef value_type *pointer; 114 typedef value_type *const_pointer; 115 116 typedef pointer iterator; 117 typedef const_pointer const_iterator; 118 typedef std::reverse_iterator<iterator> reverse_iterator; 119 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 120 121 private: 122 template <typename Char> 123 using if_compatible_char = typename std::enable_if<QtPrivate::IsCompatibleCharType<Char>::value, bool>::type; 124 125 template <typename Array> 126 using if_compatible_array = typename std::enable_if<QtPrivate::IsCompatibleArray<Array>::value, bool>::type; 127 128 template <typename Pointer> 129 using if_compatible_pointer = typename std::enable_if<QtPrivate::IsCompatiblePointer<Pointer>::value, bool>::type; 130 131 template <typename T> 132 using if_compatible_string = typename std::enable_if<QtPrivate::IsCompatibleStdBasicString<T>::value, bool>::type; 133 134 template <typename T> 135 using if_compatible_qstring_like = typename std::enable_if<std::is_same<T, QString>::value || std::is_same<T, QStringRef>::value, bool>::type; 136 137 template <typename Char, size_t N> 138 static Q_DECL_CONSTEXPR qsizetype lengthHelperArray(const Char (&)[N]) noexcept 139 { 140 return qsizetype(N - 1); 141 } 142 143 template <typename Char> 144 static qsizetype lengthHelperPointer(const Char *str) noexcept 145 { 146 #if defined(Q_CC_GNU) && !defined(Q_CC_CLANG) && !defined(Q_CC_INTEL) 147 if (__builtin_constant_p(*str)) { 148 qsizetype result = 0; 149 while (*str++) 150 ++result; 151 return result; 152 } 153 #endif 154 return QtPrivate::qustrlen(reinterpret_cast<const ushort *>(str)); 155 } 156 static qsizetype lengthHelperPointer(const QChar *str) noexcept 157 { 158 return QtPrivate::qustrlen(reinterpret_cast<const ushort *>(str)); 159 } 160 161 template <typename Char> 162 static const storage_type *castHelper(const Char *str) noexcept 163 { return reinterpret_cast<const storage_type*>(str); } 164 static Q_DECL_CONSTEXPR const storage_type *castHelper(const storage_type *str) noexcept 165 { return str; } 166 167 public: 168 Q_DECL_CONSTEXPR QStringView() noexcept 169 : m_size(0), m_data(nullptr) {} 170 Q_DECL_CONSTEXPR QStringView(std::nullptr_t) noexcept 171 : QStringView() {} 172 173 template <typename Char, if_compatible_char<Char> = true> 174 Q_DECL_CONSTEXPR QStringView(const Char *str, qsizetype len) 175 : m_size((Q_ASSERT(len >= 0), Q_ASSERT(str || !len), len)), 176 m_data(castHelper(str)) {} 177 178 template <typename Char, if_compatible_char<Char> = true> 179 Q_DECL_CONSTEXPR QStringView(const Char *f, const Char *l) 180 : QStringView(f, l - f) {} 181 182 #ifdef Q_CLANG_QDOC 183 template <typename Char, size_t N> 184 Q_DECL_CONSTEXPR QStringView(const Char (&array)[N]) noexcept; 185 186 template <typename Char> 187 Q_DECL_CONSTEXPR QStringView(const Char *str) noexcept; 188 #else 189 #if QT_DEPRECATED_SINCE(5, 14) 190 template <typename Array, if_compatible_array<Array> = true> 191 QT_DEPRECATED_VERSION_X_5_14(R"(Use u"~~~" or QStringView(u"~~~") instead of QStringViewLiteral("~~~"))") 192 Q_DECL_CONSTEXPR QStringView(const Array &str, QtPrivate::Deprecated_t) noexcept 193 : QStringView(str, lengthHelperArray(str)) {} 194 #endif // QT_DEPRECATED_SINCE 195 196 template <typename Array, if_compatible_array<Array> = true> 197 Q_DECL_CONSTEXPR QStringView(const Array &str) noexcept 198 : QStringView(str, lengthHelperArray(str)) {} 199 200 template <typename Pointer, if_compatible_pointer<Pointer> = true> 201 Q_DECL_CONSTEXPR QStringView(const Pointer &str) noexcept 202 : QStringView(str, str ? lengthHelperPointer(str) : 0) {} 203 #endif 204 205 #ifdef Q_CLANG_QDOC 206 QStringView(const QString &str) noexcept; 207 QStringView(const QStringRef &str) noexcept; 208 #else 209 template <typename String, if_compatible_qstring_like<String> = true> 210 QStringView(const String &str) noexcept 211 : QStringView(str.isNull() ? nullptr : str.data(), qsizetype(str.size())) {} 212 #endif 213 214 template <typename StdBasicString, if_compatible_string<StdBasicString> = true> 215 Q_DECL_CONSTEXPR QStringView(const StdBasicString &str) noexcept 216 : QStringView(str.data(), qsizetype(str.size())) {} 217 218 Q_REQUIRED_RESULT inline QString toString() const; // defined in qstring.h 219 220 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR qsizetype size() const noexcept { return m_size; } 221 Q_REQUIRED_RESULT const_pointer data() const noexcept { return reinterpret_cast<const_pointer>(m_data); } 222 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR const storage_type *utf16() const noexcept { return m_data; } 223 224 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar operator[](qsizetype n) const 225 { return Q_ASSERT(n >= 0), Q_ASSERT(n < size()), QChar(m_data[n]); } 226 227 // 228 // QString API 229 // 230 231 template <typename...Args> 232 Q_REQUIRED_RESULT inline QString arg(Args &&...args) const; // defined in qstring.h 233 234 Q_REQUIRED_RESULT QByteArray toLatin1() const { return QtPrivate::convertToLatin1(*this); } 235 Q_REQUIRED_RESULT QByteArray toUtf8() const { return QtPrivate::convertToUtf8(*this); } 236 Q_REQUIRED_RESULT QByteArray toLocal8Bit() const { return QtPrivate::convertToLocal8Bit(*this); } 237 Q_REQUIRED_RESULT inline QVector<uint> toUcs4() const; // defined in qvector.h 238 239 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar at(qsizetype n) const { return (*this)[n]; } 240 241 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView mid(qsizetype pos) const 242 { 243 return QStringView(m_data + qBound(qsizetype(0), pos, m_size), m_size - qBound(qsizetype(0), pos, m_size)); 244 } 245 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView mid(qsizetype pos, qsizetype n) const 246 { 247 return QStringView(m_data + qBound(qsizetype(0), pos, m_size), qBound(qsizetype(0), pos + n, m_size) - qBound(qsizetype(0), pos, m_size)); 248 } 249 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView left(qsizetype n) const 250 { 251 return QStringView(m_data, (size_t(n) > size_t(m_size) ? m_size : n)); 252 } 253 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView right(qsizetype n) const 254 { 255 return QStringView(m_data + m_size - (size_t(n) > size_t(m_size) ? m_size : n), (size_t(n) > size_t(m_size) ? m_size : n)); 256 } 257 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView chopped(qsizetype n) const 258 { return Q_ASSERT(n >= 0), Q_ASSERT(n <= size()), QStringView(m_data, m_size - n); } 259 260 Q_DECL_RELAXED_CONSTEXPR void truncate(qsizetype n) 261 { Q_ASSERT(n >= 0); Q_ASSERT(n <= size()); m_size = n; } 262 Q_DECL_RELAXED_CONSTEXPR void chop(qsizetype n) 263 { Q_ASSERT(n >= 0); Q_ASSERT(n <= size()); m_size -= n; } 264 265 Q_REQUIRED_RESULT QStringView trimmed() const noexcept { return QtPrivate::trimmed(*this); } 266 267 Q_REQUIRED_RESULT int compare(QStringView other, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept 268 { return QtPrivate::compareStrings(*this, other, cs); } 269 Q_REQUIRED_RESULT inline int compare(QLatin1String other, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept; 270 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR int compare(QChar c) const noexcept 271 { return size() >= 1 ? compare_single_char_helper(*utf16() - c.unicode()) : -1; } 272 Q_REQUIRED_RESULT int compare(QChar c, Qt::CaseSensitivity cs) const noexcept 273 { return QtPrivate::compareStrings(*this, QStringView(&c, 1), cs); } 274 275 Q_REQUIRED_RESULT bool startsWith(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept 276 { return QtPrivate::startsWith(*this, s, cs); } 277 Q_REQUIRED_RESULT inline bool startsWith(QLatin1String s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept; 278 Q_REQUIRED_RESULT bool startsWith(QChar c) const noexcept 279 { return !empty() && front() == c; } 280 Q_REQUIRED_RESULT bool startsWith(QChar c, Qt::CaseSensitivity cs) const noexcept 281 { return QtPrivate::startsWith(*this, QStringView(&c, 1), cs); } 282 283 Q_REQUIRED_RESULT bool endsWith(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept 284 { return QtPrivate::endsWith(*this, s, cs); } 285 Q_REQUIRED_RESULT inline bool endsWith(QLatin1String s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept; 286 Q_REQUIRED_RESULT bool endsWith(QChar c) const noexcept 287 { return !empty() && back() == c; } 288 Q_REQUIRED_RESULT bool endsWith(QChar c, Qt::CaseSensitivity cs) const noexcept 289 { return QtPrivate::endsWith(*this, QStringView(&c, 1), cs); } 290 291 Q_REQUIRED_RESULT qsizetype indexOf(QChar c, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept 292 { return QtPrivate::findString(*this, from, QStringView(&c, 1), cs); } 293 Q_REQUIRED_RESULT qsizetype indexOf(QStringView s, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept 294 { return QtPrivate::findString(*this, from, s, cs); } 295 Q_REQUIRED_RESULT inline qsizetype indexOf(QLatin1String s, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept; 296 297 Q_REQUIRED_RESULT bool contains(QChar c, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept 298 { return indexOf(QStringView(&c, 1), 0, cs) != qsizetype(-1); } 299 Q_REQUIRED_RESULT bool contains(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept 300 { return indexOf(s, 0, cs) != qsizetype(-1); } 301 Q_REQUIRED_RESULT inline bool contains(QLatin1String s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept; 302 303 Q_REQUIRED_RESULT inline qsizetype count(QChar c, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept; 304 Q_REQUIRED_RESULT inline qsizetype count(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept; 305 306 Q_REQUIRED_RESULT qsizetype lastIndexOf(QChar c, qsizetype from = -1, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept 307 { return QtPrivate::lastIndexOf(*this, from, QStringView(&c, 1), cs); } 308 Q_REQUIRED_RESULT qsizetype lastIndexOf(QStringView s, qsizetype from = -1, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept 309 { return QtPrivate::lastIndexOf(*this, from, s, cs); } 310 Q_REQUIRED_RESULT inline qsizetype lastIndexOf(QLatin1String s, qsizetype from = -1, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept; 311 312 Q_REQUIRED_RESULT bool isRightToLeft() const noexcept 313 { return QtPrivate::isRightToLeft(*this); } 314 Q_REQUIRED_RESULT bool isValidUtf16() const noexcept 315 { return QtPrivate::isValidUtf16(*this); } 316 317 Q_REQUIRED_RESULT inline short toShort(bool *ok = nullptr, int base = 10) const; 318 Q_REQUIRED_RESULT inline ushort toUShort(bool *ok = nullptr, int base = 10) const; 319 Q_REQUIRED_RESULT inline int toInt(bool *ok = nullptr, int base = 10) const; 320 Q_REQUIRED_RESULT inline uint toUInt(bool *ok = nullptr, int base = 10) const; 321 Q_REQUIRED_RESULT inline long toLong(bool *ok = nullptr, int base = 10) const; 322 Q_REQUIRED_RESULT inline ulong toULong(bool *ok = nullptr, int base = 10) const; 323 Q_REQUIRED_RESULT inline qlonglong toLongLong(bool *ok = nullptr, int base = 10) const; 324 Q_REQUIRED_RESULT inline qulonglong toULongLong(bool *ok = nullptr, int base = 10) const; 325 Q_REQUIRED_RESULT inline float toFloat(bool *ok = nullptr) const; 326 Q_REQUIRED_RESULT inline double toDouble(bool *ok = nullptr) const; 327 328 Q_REQUIRED_RESULT inline int toWCharArray(wchar_t *array) const; // defined in qstring.h 329 330 Q_REQUIRED_RESULT inline 331 QList<QStringView> split(QStringView sep, 332 Qt::SplitBehavior behavior = Qt::KeepEmptyParts, 333 Qt::CaseSensitivity cs = Qt::CaseSensitive) const; 334 Q_REQUIRED_RESULT inline 335 QList<QStringView> split(QChar sep, Qt::SplitBehavior behavior = Qt::KeepEmptyParts, 336 Qt::CaseSensitivity cs = Qt::CaseSensitive) const; 337 338 #if QT_CONFIG(regularexpression) 339 Q_REQUIRED_RESULT inline 340 QList<QStringView> split(const QRegularExpression &sep, Qt::SplitBehavior behavior = Qt::KeepEmptyParts) const; 341 #endif 342 343 // 344 // STL compatibility API: 345 // 346 Q_REQUIRED_RESULT const_iterator begin() const noexcept { return data(); } 347 Q_REQUIRED_RESULT const_iterator end() const noexcept { return data() + size(); } 348 Q_REQUIRED_RESULT const_iterator cbegin() const noexcept { return begin(); } 349 Q_REQUIRED_RESULT const_iterator cend() const noexcept { return end(); } 350 Q_REQUIRED_RESULT const_reverse_iterator rbegin() const noexcept { return const_reverse_iterator(end()); } 351 Q_REQUIRED_RESULT const_reverse_iterator rend() const noexcept { return const_reverse_iterator(begin()); } 352 Q_REQUIRED_RESULT const_reverse_iterator crbegin() const noexcept { return rbegin(); } 353 Q_REQUIRED_RESULT const_reverse_iterator crend() const noexcept { return rend(); } 354 355 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR bool empty() const noexcept { return size() == 0; } 356 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar front() const { return Q_ASSERT(!empty()), QChar(m_data[0]); } 357 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar back() const { return Q_ASSERT(!empty()), QChar(m_data[m_size - 1]); } 358 359 // 360 // Qt compatibility API: 361 // 362 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR bool isNull() const noexcept { return !m_data; } 363 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR bool isEmpty() const noexcept { return empty(); } 364 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR int length() const /* not nothrow! */ 365 { return Q_ASSERT(int(size()) == size()), int(size()); } 366 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar first() const { return front(); } 367 Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar last() const { return back(); } 368 private: 369 qsizetype m_size; 370 const storage_type *m_data; 371 372 Q_DECL_CONSTEXPR int compare_single_char_helper(int diff) const noexcept 373 { return diff ? diff : size() > 1 ? 1 : 0; } 374 }; 375 Q_DECLARE_TYPEINFO(QStringView, Q_PRIMITIVE_TYPE); 376 377 template <typename QStringLike, typename std::enable_if< 378 std::is_same<QStringLike, QString>::value || std::is_same<QStringLike, QStringRef>::value, 379 bool>::type = true> 380 inline QStringView qToStringViewIgnoringNull(const QStringLike &s) noexcept 381 { return QStringView(s.data(), s.size()); } 382 383 QT_END_NAMESPACE 384 385 #endif /* QSTRINGVIEW_H */ 386