Improve readability of code that uses the Qt signed size typev5.10.0-rc2

During the container BoF session at the Qt Contributor Summit 2017 the
name of the signed size type became a subject of discussion in the
context of readability of code using this type and the intention of
using it for all length, size and count properties throughout the entire
framework in future versions of Qt.

This change proposes qsizetype as new name for qssize_t to emphasize the
readability of code over POSIX compatibility, the former being
potentially more relevant than the latter to the majority of users of
Qt.

Change-Id: Idb99cb4a8782703c054fa463a9e5af23a918e7f3
Reviewed-by: Samuel Gaist <samuel.gaist@edeltech.ch>
Reviewed-by: David Faure <david.faure@kdab.com>

1 files changed, 20 insertions, 20 deletions

diff --git a/src/corelib/tools/qstringview.h b/src/corelib/tools/qstringview.h
index 14405f325d..903d7ccb24 100644
--- a/src/corelib/tools/qstringview.h
+++ b/src/corelib/tools/qstringview.h
@@ -111,7 +111,7 @@ public:
 #endif
     typedef const QChar value_type;
     typedef std::ptrdiff_t difference_type;
-    typedef qssize_t size_type;
+    typedef qsizetype size_type;
     typedef value_type &reference;
     typedef value_type &const_reference;
     typedef value_type *pointer;
@@ -139,24 +139,24 @@ private:
     using if_compatible_qstring_like = typename std::enable_if<std::is_same<T, QString>::value || std::is_same<T, QStringRef>::value, bool>::type;
 
     template <typename Char, size_t N>
-    static Q_DECL_CONSTEXPR qssize_t lengthHelperArray(const Char (&)[N]) Q_DECL_NOTHROW
+    static Q_DECL_CONSTEXPR qsizetype lengthHelperArray(const Char (&)[N]) Q_DECL_NOTHROW
     {
-        return qssize_t(N - 1);
+        return qsizetype(N - 1);
     }
 
     template <typename Char>
-    static qssize_t lengthHelperPointer(const Char *str) Q_DECL_NOTHROW
+    static qsizetype lengthHelperPointer(const Char *str) Q_DECL_NOTHROW
     {
 #if defined(Q_CC_GNU) && !defined(Q_CC_CLANG) && !defined(Q_CC_INTEL)
         if (__builtin_constant_p(*str)) {
-            qssize_t result = 0;
+            qsizetype result = 0;
             while (*str++)
                 ++result;
         }
 #endif
         return QtPrivate::qustrlen(reinterpret_cast<const ushort *>(str));
     }
-    static qssize_t lengthHelperPointer(const QChar *str) Q_DECL_NOTHROW
+    static qsizetype lengthHelperPointer(const QChar *str) Q_DECL_NOTHROW
     {
         return QtPrivate::qustrlen(reinterpret_cast<const ushort *>(str));
     }
@@ -174,7 +174,7 @@ public:
         : QStringView() {}
 
     template <typename Char, if_compatible_char<Char> = true>
-    Q_DECL_CONSTEXPR QStringView(const Char *str, qssize_t len)
+    Q_DECL_CONSTEXPR QStringView(const Char *str, qsizetype len)
         : m_size((Q_ASSERT(len >= 0), Q_ASSERT(str || !len), len)),
           m_data(castHelper(str)) {}
 
@@ -204,20 +204,20 @@ public:
 #else
     template <typename String, if_compatible_qstring_like<String> = true>
     QStringView(const String &str) Q_DECL_NOTHROW
-        : QStringView(str.isNull() ? nullptr : str.data(), qssize_t(str.size())) {}
+        : QStringView(str.isNull() ? nullptr : str.data(), qsizetype(str.size())) {}
 #endif
 
     template <typename StdBasicString, if_compatible_string<StdBasicString> = true>
     QStringView(const StdBasicString &str) Q_DECL_NOTHROW
-        : QStringView(str.data(), qssize_t(str.size())) {}
+        : QStringView(str.data(), qsizetype(str.size())) {}
 
     Q_REQUIRED_RESULT inline QString toString() const; // defined in qstring.h
 
-    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR qssize_t size() const Q_DECL_NOTHROW { return m_size; }
+    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR qsizetype size() const Q_DECL_NOTHROW { return m_size; }
     Q_REQUIRED_RESULT const_pointer data() const Q_DECL_NOTHROW { return reinterpret_cast<const_pointer>(m_data); }
     Q_REQUIRED_RESULT Q_DECL_CONSTEXPR const storage_type *utf16() const Q_DECL_NOTHROW { return m_data; }
 
-    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar operator[](qssize_t n) const
+    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar operator[](qsizetype n) const
     { return Q_ASSERT(n >= 0), Q_ASSERT(n < size()), QChar(m_data[n]); }
 
     //
@@ -229,22 +229,22 @@ public:
     Q_REQUIRED_RESULT QByteArray toLocal8Bit() const { return QtPrivate::convertToLocal8Bit(*this); }
     Q_REQUIRED_RESULT inline QVector<uint> toUcs4() const; // defined in qvector.h
 
-    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar at(qssize_t n) const { return (*this)[n]; }
+    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar at(qsizetype n) const { return (*this)[n]; }
 
-    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView mid(qssize_t pos) const
+    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView mid(qsizetype pos) const
     { return Q_ASSERT(pos >= 0), Q_ASSERT(pos <= size()), QStringView(m_data + pos, m_size - pos); }
-    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView mid(qssize_t pos, qssize_t n) const
+    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView mid(qsizetype pos, qsizetype n) const
     { return Q_ASSERT(pos >= 0), Q_ASSERT(n >= 0), Q_ASSERT(pos + n <= size()), QStringView(m_data + pos, n); }
-    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView left(qssize_t n) const
+    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView left(qsizetype n) const
     { return Q_ASSERT(n >= 0), Q_ASSERT(n <= size()), QStringView(m_data, n); }
-    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView right(qssize_t n) const
+    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView right(qsizetype n) const
     { return Q_ASSERT(n >= 0), Q_ASSERT(n <= size()), QStringView(m_data + m_size - n, n); }
-    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView chopped(qssize_t n) const
+    Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QStringView chopped(qsizetype n) const
     { return Q_ASSERT(n >= 0), Q_ASSERT(n <= size()), QStringView(m_data, m_size - n); }
 
-    Q_DECL_RELAXED_CONSTEXPR void truncate(qssize_t n)
+    Q_DECL_RELAXED_CONSTEXPR void truncate(qsizetype n)
     { Q_ASSERT(n >= 0); Q_ASSERT(n <= size()); m_size = n; }
-    Q_DECL_RELAXED_CONSTEXPR void chop(qssize_t n)
+    Q_DECL_RELAXED_CONSTEXPR void chop(qsizetype n)
     { Q_ASSERT(n >= 0); Q_ASSERT(n <= size()); m_size -= n; }
 
     Q_REQUIRED_RESULT QStringView trimmed() const Q_DECL_NOTHROW { return QtPrivate::trimmed(*this); }
@@ -291,7 +291,7 @@ public:
     Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar first() const { return front(); }
     Q_REQUIRED_RESULT Q_DECL_CONSTEXPR QChar last()  const { return back(); }
 private:
-    qssize_t m_size;
+    qsizetype m_size;
     const storage_type *m_data;
 };
 Q_DECLARE_TYPEINFO(QStringView, Q_PRIMITIVE_TYPE);