当我尝试在MSVC2013中使用“QJsonObject::iterator”时,遇到了一个奇怪的错误。
我有以下示例:
#include <QCoreApplication>
#include <QJsonObject>
#include <QDebug>
#include <algorithm>
void processValue(QJsonValue value) {
qDebug() << value.toString();
}
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
QJsonObject jsonObject;
jsonObject.insert("a", "A");
jsonObject.insert("b", "B");
jsonObject.insert("c", "C");
jsonObject.insert("d", "D");
jsonObject.insert("e", "E");
std::for_each (jsonObject.begin(), jsonObject.end(), processValue);
return a.exec();
}
这段代码在MSVC2008(交叉编译到WinCE)和MinGW上编译和运行,但在MSVC2013上则不然。在所有情况下,我都使用Qt 5.5.1。
错误消息为:
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\xutility(375) : error C2039: 'pointer' : is not a member of 'QJsonObject::iterator'
c:\qt\qt5.5.1msvc\5.5\msvc2013\include\qtcore\qjsonobject.h(96) : see declaration of 'QJsonObject::iterator'
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\xutility(584) : see reference to class template instantiation 'std::iterator_traits<_InIt>' being compiled
with
[
_InIt=QJsonObject::iterator
]
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\algorithm(31) : see reference to function template instantiation 'void std::_Debug_range<_InIt>(_InIt,_InIt,std::_Dbfile_t,std::_Dbline_t)' being compiled
with
[
_InIt=QJsonObject::iterator
]
..\QJsonObjectIteratorIssue\main.cpp(21) : see reference to function template instantiation '_Fn1 std::for_each<QJsonObject::iterator,void(__cdecl *)(QJsonValue)>(_InIt,_InIt,_Fn1)' being compiled
with
[
_Fn1=void (__cdecl *)(QJsonValue)
, _InIt=QJsonObject::iterator
]
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\xutility(375) : error C2146: syntax error : missing ';' before identifier 'pointer'
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\xutility(375) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\xutility(375) : error C2602: 'std::iterator_traits<_InIt>::pointer' is not a member of a base class of 'std::iterator_traits<_InIt>'
with
[
_InIt=QJsonObject::iterator
]
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\xutility(375) : see declaration of 'std::iterator_traits<_InIt>::pointer'
with
[
_InIt=QJsonObject::iterator
]
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\xutility(375) : error C2868: 'std::iterator_traits<_InIt>::pointer' : illegal syntax for using-declaration; expected qualified-name
with
[
_InIt=QJsonObject::iterator
]
我是否在这里做错了什么,这只是碰巧在另外两个编译器上工作?
