C++ 为什么字符串没有在范围内声明
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why is string not declared in scope
提问by Jimm
I have the following code:
我有以下代码：
#include <string>
#include <boost/thread/tss.hpp>
static boost::thread_specific_ptr<string> _tssThreadNameSptr;
I get the following error
我收到以下错误
g++ -c -I$BOOST_PATH tssNaming.h
tssNaming.h:7: error: 'string' was not declared in this scope
g++ -c -I$BOOST_PATH tssNaming.h
tssNaming.h:7: 错误: 'string' 未在此范围内声明
But I am including string in my #include.
但我在我的#include.
回答by Rapptz
You have to use std::stringsince it's in the stdnamespace.
您必须使用，std::string因为它在std命名空间中。
回答by Jimm
stringis in the stdnamespace. You have the following options:
string位于std命名空间中。您有以下选择：
- Write
using namespace std;after the include and enable all thestdnames: then you can write onlystringon your program. - Write
using std::stringafter the include to enablestd::string: then you can write onlystringon your program. - Use
std::stringinstead ofstring
using namespace std;在包含之后写入并启用所有std名称：然后您只能string在您的程序上写入。using std::string在包含后写入以启用std::string：然后您只能string在您的程序上写入。- 使用
std::string代替string
回答by Nuelsian
I find that including:
我发现包括：
using namespace std;
To your C++ code saves a lot of time in debugging especially in situations like yours where std:: string is required and also it will help in keeping your code clean.
您的 C++ 代码可以节省大量调试时间，尤其是在像您这样需要 std:: string 的情况下，它还有助于保持代码清洁。
With this in mind, your code should be:
考虑到这一点，您的代码应该是：
#include <string>
using namespace std;
#include <boost/thread/tss.hpp>
static boost::thread_specific_ptr<string> _tssThreadNameSptr;
