Ｃ＋＋ 重载运算符
[user:lib_hdmanage] cat example/test6.cpp
/// @file test6.cpp
/// @brief
/// @author Easton Woo
/// 0.01
#include <stdio.h>
class CGlobal
{
public:
CGlobal(int i = 1) : m_value(i){};
int m_value;
};
CGlobal & operator<<(CGlobal & main, CGlobal & param) //相当于 main.func(param),返回值为main对象
{
_print_int(param.m_value);
main.m_value += param.m_value;
_print_int(main.m_value);
return main;
}
class CTest
{
public:
CTest(int i = 1):m_value(i){};
CTest & operator>>(CTest & ct) // 有了this指针，第一个参数就可以不要了。
{
_print_int(ct.m_value);
m_value += ct.m_value;
_print_int(m_value);
return *this;
}
int m_value ;
};
int main(int argc, char const* argv[])
{
#if 0
CTest t1(1),t2(3),t3(5);
t1>>t2>>t3; // 可以这么理解：t1>>t2相当于t1.func(t2),返回t1类对象后和>>t3组成新的函数t1.func(t2),再次返回t1类对象.
_print_int(t1.m_value);
_print_int(t2.m_value);
_print_int(t3.m_value);
#else
CGlobal t1(1),t2(3),t3(5);
t1<<t2<<t3;
_print_int(t1.m_value);
_print_int(t2.m_value);
_print_int(t3.m_value);
#endif
return 0;
}
[user:lib_hdmanage] m example && ./example/test6.i386.elf
Makefile:4: test
Makefile:5: example
[i386] make -> hdmanage example/test6.i386.elf ...
param.m_value = 3 example/test6.cpp : operator<<() : 18
main.m_value = 4 example/test6.cpp : operator<<() : 20
param.m_value = 5 example/test6.cpp : operator<<() : 18
main.m_value = 9 example/test6.cpp : operator<<() : 20
t1.m_value = 9 example/test6.cpp : main() : 53
t2.m_value = 3 example/test6.cpp : main() : 54
t3.m_value = 5 example/test6.cpp : main() : 55
[user:lib_hdmanage]
如果把#if 0 改成#if 1
[user:lib_hdmanage] m example && ./example/test6.i386.elf
Makefile:4: test
Makefile:5: example
[i386] make -> hdmanage example/test6.i386.elf ...
ct.m_value = 3 example/test6.cpp : operator>>() : 31
m_value = 4 example/test6.cpp : operator>>() : 33
ct.m_value = 5 example/test6.cpp : operator>>() : 31
m_value = 9 example/test6.cpp : operator>>() : 33
t1.m_value = 9 example/test6.cpp : main() : 46
t2.m_value = 3 example/test6.cpp : main() : 47
t3.m_value = 5 example/test6.cpp : main() : 48