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Remove pre-C++17 code path

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Change-Id: Iaa7f677f45cee50f0b9ed236cf5bef18d5764bfa
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
This commit is contained in:
Lars Knoll 2020-09-08 14:44:32 +02:00
parent 0078391c18
commit 05acc167c9
1 changed files with 0 additions and 17 deletions
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17
src/corelib/global/qglobal.h
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@ -1065,29 +1065,12 @@ QForeachContainer<typename std::decay<T>::type> qMakeForeachContainer(T &&t)
}
#if __cplusplus >= 201703L
// Use C++17 if statement with initializer. User's code ends up in a else so
// scoping of different ifs is not broken
#define Q_FOREACH(variable, container) \
for (auto _container_ = QtPrivate::qMakeForeachContainer(container); \
_container_.i != _container_.e; ++_container_.i) \
if (variable = *_container_.i; false) {} else
#else
// Explanation of the control word:
// - it's initialized to 1
// - that means both the inner and outer loops start
// - if there were no breaks, at the end of the inner loop, it's set to 0, which
// causes it to exit (the inner loop is run exactly once)
// - at the end of the outer loop, it's inverted, so it becomes 1 again, allowing
// the outer loop to continue executing
// - if there was a break inside the inner loop, it will exit with control still
// set to 1; in that case, the outer loop will invert it to 0 and will exit too
#define Q_FOREACH(variable, container) \
for (auto _container_ = QtPrivate::qMakeForeachContainer(container); \
_container_.control && _container_.i != _container_.e; \
++_container_.i, _container_.control ^= 1) \
for (variable = *_container_.i; _container_.control; _container_.control = 0)
#endif
#endif // QT_NO_FOREACH
#define Q_FOREVER for(;;)