C++矢量文字,或类似的东西

Question

我正在编写一些针对C++ API的代码,它采用向量向量的向量,并且编写如下代码的代码变得乏味:

vector<string> vs1;
vs1.push_back("x");
vs1.push_back("y");
...
vector<string> vs2;
...
vector<vector<string> > vvs1;
vvs1.push_back(vs1);
vvs1.push_back(vs2);
...
vector<vector<string> > vvs2;
...
vector<vector<vector<string> > > vvvs;
vvvs.push_back(vvs1);
vvvs.push_back(vvs2);
...

C++是否有矢量文字语法？即,类似于:

vector<vector<vector<string>>> vvvs = 
    { { {"x","y", ... }, ... }, ... }

有没有非内置的方法来实现这一目标？

Answer 1

在C++ 0x中,您将能够使用所需的语法:

vector<vector<vector<string> > > vvvs = 
    { { {"x","y", ... }, ... }, ... };

但是在今天的C++中,你只能使用boost.assign来实现:

vector<string> vs1;
vs1 += "x", "y", ...;
vector<string> vs2;
...
vector<vector<string> > vvs1;
vvs1 += vs1, vs2, ...;
vector<vector<string> > vvs2;
...
vector<vector<vector<string> > > vvvs;
vvvs += vvs1, vvs2, ...;

...或使用Qt的容器,让你一次性完成:

QVector<QVector<QVector<string> > > vvvs =
    QVector<QVector<QVector<string> > >() << (
        QVector<QVector<string> >() << (
            QVector<string>() << "x", "y", ...) <<
            ... ) <<
        ...
    ;

另一个半合理选项,至少对于平面向量,是从数组构造:

string a[] = { "x", "y", "z" };
vector<string> vec(a, a + 3);

Answer 2

查看Boost分配库.