c++

示例：

#include <vector>
#include <string>
#include <iostream>
#include <functional>

using namespace std;

std::function<int (int)> Functional;


int testFunc(int i) {
    return i;
}

auto lambda = [](int i) -> int { return i; };

class Functor {
public:
    int operator()(int i) {
        return i;
    }
};

class test{
public:
    int foo(int i) { return i; }
    static int staticFunc(int i) { return i; }
};

int  main() {
    Functional = testFunc;
    std::cout << "普通函数：" << Functional(1) << std::endl;

    Functional = lambda;
    std::cout << "lambda函数:" << Functional(2) << std::endl;

    Functor functor;
    Functional = functor;
    std::cout << "仿函数:" << Functional(3) << std::endl;

    test ctest;
    Functional = test::staticFunc;
    std::cout << "类静态函数:" << Functional(4) << std::endl;

    Functional = std::bind(&test::foo, ctest, std::placeholders::_1);
    std::cout << "类成员函数:" << Functional(5) << std::endl;

    std::cin.get();
    return 0;
}

占个坑先