C++中的function

#include<iostream>
#include<functional>

学习C++中的function，记下，免得忘了。

更详细的可以看这里

int powerFunc(int x)
{
    return x << 1;
}
struct test
{
public:
    test(int aa) :m_test(aa) {}
    ~test() {}
    int RetMemValue(int offset)
    {
        return m_test << offset;
    }
private:
    int m_test;
};
struct OutValue
{
    void operator()(int value,int offset) const
    {
        cout << (value << offset) << endl;
    }
};

int    main(int argc, char **argv)
{
    //Free function
    std::function<int(int)> p_power = powerFunc;
    cout << p_power(5) << endl;
    //lambda
    std::function<int()> p_lambda = []() {return powerFunc(6); };
    cout << p_lambda() << endl;
    //bind
    std::function<int()> p_bind = std::bind(powerFunc, 7);
    cout << p_bind() << endl;
    //mem function
    std::function<int(test&,int)> p_memFunc = &test::RetMemValue;
    test obj_test(8);
    cout << p_memFunc(obj_test, 2) << endl;
　　//function obj
    std::function<void(int, int)> p_memAndValue = OutValue();
    p_memAndValue(9, 2);
}