c++ lambda表达式捕获类数据…

lambda表达式允许捕获局部变量，但是数据成员不是局部变量。用一种特殊的方法，你可以捕获“this”：。
using namespace std;
class Kitty {
 public:
     explicit Kitty(int toys) : m_toys(toys) { }    void meow(const vector& v) const {
         for_each(v.begin(), v.end(), [this](int n) {
             cout << "If you gave me " << n << " toys, I would have " << n + m_toys << " toys total." << endl;
         });
     }private:
     int m_toys;
 };int main() {
     vector v;    for (int i = 0; i < 3; ++i) {
         v.push_back(i);
     }    Kitty k(5);
     k.meow(v);
 }If you gave me 0 toys, I would have 5 toys total.
 If you gave me 1 toys, I would have 6 toys total.
 If you gave me 2 toys, I would have 7 toys total.当你捕获了this以后，m_toys就可以使用了，它隐式的表示this->m_toys，你也可以显示的说明this->m_toys。（在lambda表达式中，只有捕获了this后才可以使用它，你永远无法得到lambda表达式本身的this指针）
你也可以隐式的捕获this：
 using namespace std;
class Kitty {
 public:
     explicit Kitty(int toys) : m_toys(toys) { }    void meow(const vector& v) const {
         for_each(v.begin(), v.end(), [=](int n) {
             cout << "If you gave me " << n << " toys, I would have " << n + m_toys << " toys total." << endl;
         });
     }private:
     int m_toys;
 };int main() {
     vector v;    for (int i = 0; i < 3; ++i) {
         v.push_back(i);
     }    Kitty k(5);
     k.meow(v);
 }C:\Temp>cl /EHsc /nologo /W4 implicitmemberkitty.cpp > NUL && implicitmemberkitty
 If you gave me 0 toys, I would have 5 toys total.
 If you gave me 1 toys, I would have 6 toys total.
 If you gave me 2 toys, I would have 7 toys total.

你也可以使用“[&]”,但是它不会影响this的捕获方式（永远按值传递）。“[&this]”是不允许的。

上面代码不是自己的，今天做到c++ primer（第五版） 13.43 遇到了问题，查了查，然后记下来了