C++11学习笔记之三lamda表达式，std::function, std::bind

//lamda
//first lamda
[]
{};

// second lamda
[]() //or no need () when paramater is null
{
std::cout << "second" << std::endl;
}();// last add(), express will call this lamda func

// 3 with return type
auto kkk = []()
{
return 1;
}();

// 4, set return type
auto kkkk = [] (int i) -> bool { return (bool)i; }(5);

//5, lamda capture, [=], [=,&], [&], [this][] 不捕获...
/*[&] 以引用的方式捕获
[=] 通过变量的一个拷贝捕获
[=, &foo] 通过变量的拷贝捕获，但是用foo变量的引用捕获
[bar] 通过复制捕获，不要复制其他
[this] 捕获this指针对应成员
*/

function, bind等，上代码

#include <iostream>
#include <functional>
using namespace std;
typedef std::function<void()> fp;
typedef std::function<void(int)> fpi1;
void g_fun()
{
std::cout << "global function bind" << std::endl;
}

class A
{
public:
static void aFunStatic()
{
std::cout << "aFunStatic" << std::endl;
}

virtual void aFun()
{
std::cout << "aFun" << std::endl;
}

void aFunI1(int i)
{
std::cout << "aFunI1:"  << i << std::endl;
}

};

class DerivedA
:public A
{
public:
virtual void aFun() override
{
std::cout << "aFun in DeriveA" << std::endl;
}
};

class B
{
public:
void bCallAFun()
{
if(callFun)
callFun();
}
void bCallAFunStatic()
{
if(callFunStatic)
callFunStatic();
}

void bCallAFunI1(int i)
{
if(callFunI1)
callFunI1(i);
}

fp callFunStatic;
fp callFun;
fpi1 callFunI1;
};

void main()
{
B b;
A a;

//bind to global function
fp f = fp(&g_fun);
f();

//bind to class function
//static
b.callFunStatic = std::bind(&A::aFunStatic);
b.bCallAFunStatic();

//no static function without parameter
b.callFun = std::bind(&A::aFun, &a);
b.bCallAFun();

//no static function with parameter
b.callFunI1 = std::bind(&A::aFunI1, &a, std::placeholders::_1);
b.bCallAFunI1(5);

//about polymorphic
DerivedA da;
b.callFun = std::bind(&A::aFun, &da);
b.bCallAFun();
}