深入学习c++--lambda函数

1. 简单使用

#include <iostream>
#include <functional>
using namespace std;

struct Print {
    void operator()(int a, int b, int c) const
    {
        cout << "a " << a << " b " << b << " c " << c << endl;
    }
};

void printInfo(int a, int b, int c)
{
    cout << "a " << a << " b " << b << " c " << c << endl;
}

template<typename T1, typename T2, typename T3>
void templatePrint(T1 a, T2 b, T3 c)
{
    cout << "a " << a << " b " << b << " c " << c << endl;
}

struct TemplatePrint {
    template<typename T1, typename T2, typename T3>
    void operator()(T1 a, T2 b, T3 c) const {
        cout << "a " << a << " b " << b << " c " << c << endl;
    }
};

template<typename Func>
void printUserFunc(Func func, int a, int b, int c)
{
    func(a, b, c);
}

int main()
{
    Print printUserClass;
    TemplatePrint printUserTempClass;

    printInfo(, , );
    templatePrint(, , );
    printUserClass(, , );
    printUserTempClass(, , );

    // lambda c++
    auto local = [](int a, int b, int c) {
        cout << "a " << a << " b " << b << " c " << c << endl;
    };
    local(, , );

    printUserFunc(local, , , );

    //lambda c++
    printUserFunc([](int a, int b, int c) {
        cout << "a " << a << " b " << b << " c " << c << endl;
    },
    , , );

    // 值拷贝
    int a = , b = , c = ;
     auto local2 = [a, b, c] () {
        cout << "a " << a << " b " << b << " c " << c << endl;
    };
    local2();

    //传引用
    auto local3 = [&] () {     // &:外部引用 和 =: 外部拷贝
        cout << "a " << a << " b " << b << " c " << c << endl;
    };
    local3(); 

    return ;
}