c++11 初始化列表 bind function 示例

// 111111111111.cpp: 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
#include <map>

class FooVector {
    std::vector<int> content_;
public:
    FooVector(std::initializer_list<int> list) {
        for (auto it = list.begin(); it != list.end(); it++) {
            content_.push_back(*it);
        }
    }
};

class FooMap {
    std::map<int, int> content_;
    using pair_t = std::map<int, int>::value_type;
public:
    FooMap(std::initializer_list<pair_t> list) {
        for (auto it = list.begin(); it != list.end(); ++it) {
            content_.insert(*it);
        }
    }
};

void test1() {
    FooVector foo_1 = { 1,2,3,4,5 };
    FooMap foo_2 = { {1,2},{3,4},{5,6} };
}

void func(std::initializer_list<int> l) {
    for (auto it = l.begin(); it != l.end(); it++) {
        std::cout << *it << std::endl;
    }
}

void test2()
{
    func({});
    func({ 1,2,3 });
}

int main()
{
    test1();
    test2();
    return 0;
}

 

// 111111111111.cpp: 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <functional>

void func(void) {
    std::cout << __FUNCTION__ << std::endl;
}

class Foo {
public:
    static int foo_func(int a) {
        std::cout << __FUNCTION__ << "(" << a << ") ->:";
        return a;
    }
};

class Bar {
public:
    int operator()(int a) {
        std::cout << __FUNCTION__ << "(" << a << ") ->: ";
        return a;
    }
};

void  test1()
{
    std::function<void(void)> fr1 = func;
    fr1();

    std::function<int(int)> fr2 = Foo::foo_func;
    std::cout << fr2(123) << std::endl;

    Bar bar;
    fr2 = bar;
    std::cout << fr2(123) << std::endl;
}
//====================================================================
class A {
    std::function<void()> callback_;
public:
    A(const std::function<void()>& f) :callback_(f) {}
    void notify(void) {
        callback_();
    }
};

class Foo0 {
public:
    void operator()(void) {
        std::cout << __FUNCTION__ << std::endl;
    }
};

void test2() {
    Foo0 foo;
    A aa(foo);
    aa.notify();
}
//================================================================
void call_when_even(int x, const std::function<void(int)>& f) {
    if (!(x & 1)) {
        f(x);
    }
}

void output(int x) {
    std::cout << x << " ";
}

void test3() {
    for (int i = 0; i < 10; i++) {
        call_when_even(i, output);
    }
    std::cout << std::endl;
}
//====================================================================
void output_add_2(int x) {
    std::cout << x + 2 << " ";
}

void test4() {
    {
        auto fr = std::bind(output, std::placeholders::_1);
        for (int i = 0; i < 10; ++i) {
            call_when_even(i, fr);
        }
        std::cout << std::endl;
    }
    {
        auto fr = std::bind(output_add_2, std::placeholders::_1);
        for (int i = 0; i < 10; ++i) {
            call_when_even(i, fr);
        }
        std::cout << std::endl;
    }
}




int main()
{
    test1();
    test2();
    test3();
    test4();
    return 0;
}