DEVOCEAN

#include <iostream>

using namespace std;

class temp_cls
{
    public:
    temp_cls(){
        pro_a = new int(5);
        printf("temp object created\n");
    }
    ~temp_cls(){
        delete pro_a;
        printf("temp object removed");
    }
    int *pro_a;
};

int main()
{
    temp_cls test;
    temp_cls *temp = &test;
    temp_cls *temp2(temp);
    cout << (*temp).pro_a << endl;
    cout << (*temp2).pro_a << endl;
    delete temp;
    printf("test val %p",(*temp2).pro_a);
    return 0;
}
/*
temp object created
a.b와 b.b가 동일한 위치를 Pointing하고 있는것을 볼 수 있습니다
0x56502926aeb0
0x56502926aeb0
double free or corruption (out)
*/

#include <iostream>

using namespace std;

class temp_cls
{
    public:
    temp_cls(void){
        pro_a = new int(5);
        printf("temp object %p created\n", this);
    }
    //int value를 받을 때 대응될 변환생성자
    explicit temp_cls(int a){
        this->pro_a = new int(a);
        printf("temp object %p created by trasnform init\n", this);
    }
    //clss object를 받을 경우의 복사생성자
    explicit temp_cls(const temp_cls &tg_obj){
        printf("temp object %p created\n", this);
        printf("receive temp_cls object. tg_obj a : %d\n", *tg_obj.pro_a);
        this->pro_a = new int (*tg_obj.pro_a);
    }
    //class pointer를 받을 경우의 복사생성자
    explicit temp_cls(temp_cls *tg_obj){
        printf("temp object %p created\n", this);
        printf("receive temp_cls pointer. tg_obj a : %d\n", *(*tg_obj).pro_a);
        this->pro_a = new int(*(tg_obj->pro_a));
    }
    ~temp_cls(){
        delete pro_a;
        printf("temp object %p removed\n", this);
    }
    //class object간 =연산을 통해서 복사할 경우
    temp_cls &operator =(const temp_cls &tg_obj){
        printf("temp object %p created\n", this);
        printf("receive temp_cls object by operator '='. tg_obj a : %d\n", *tg_obj.pro_a);
        this->pro_a = new int (*tg_obj.pro_a);
        return *this;
    }

    int *pro_a;
};

int main()
{
    temp_cls test123;
    temp_cls test(10);
    temp_cls test_op(30);
    test_op = test;
    temp_cls *temp = new temp_cls(test);
    temp_cls *temp2 = new temp_cls(temp);
    cout << (*temp).pro_a << endl;
    cout << (*temp2).pro_a << endl;
    delete temp;
    printf("test val %p is alive \n",(*temp2).pro_a);
    return 0;
}
/*
(test123 obj)temp object 0x7ffe49d54740 created
(test obj)temp object 0x7ffeb6649a68 created by trasnform init
(test_op obj)temp object 0x7ffeb6649a70 created by trasnform init
(test_op obj =operation)temp object 0x7ffeb6649a70 created
(test_op obj =operation)receive temp_cls object by operator '='. tg_obj a : 5
(temp pointer)temp object 0x55954cd76320 created
(temp pointer)receive temp_cls object. tg_obj a : 5
(temp2 pointer)temp object 0x55954cd76360 created
(temp2 pointer)receive temp_cls pointer. tg_obj a : 5
0x55954cd76340
0x55954cd76380
(temp pointer)temp object 0x55954cd76320 removed
(temp2 pointer)test val 0x55954cd76380 is alive 
(test pointer)temp object 0x7ffeb6649a70 removed
(test_op pointer)temp object 0x7ffeb6649a68 removed
*/

class temp_cls:
    def __init__(self, a=None, b=None):
        self.a = a
        self.b = b

import copy
if __name__ == "__main__":
    temp = temp_cls(1, [20,54,62,3,9])
    #C++의 temp_cls temp2(temp);
    #를 얕은복사 형식으로 사용한것과 같은 기능을 합니다.
    temp2 = copy.copy(temp)    
    print(temp is temp2)
    print(temp.b is temp2.b)
    del temp
    print(temp2.b)
'''
temp과 temp2가 같은지 여부 : False
temp.b와 temp2.b가 같은지 여부 : True
temp를 삭제한 뒤 temp2.b : [20, 54, 62, 3, 9]
'''

'''
type의 종류에 따라 copy function을 정의
list, dict, set, bytearray는 PyListObject처럼
CPython에서 정의된 copy방법을 사용
PyList의 경우
static PyObject *
list_copy_impl(PyListObject *self)
{
    return list_slice(self, 0, Py_SIZE(self));
}

이 외에 immutable Object의 경우
함수의 매개변수로 투입 -> 합수의 return으로 반환
의 방법으로 객체의 얕은복사
'''
_copy_dispatch = d = {}

def _copy_immutable(x):
    return x
for t in (type(None), int, float, bool, complex, str, tuple,
          bytes, frozenset, type, range, slice, property,
          types.BuiltinFunctionType, type(Ellipsis), type(NotImplemented),
          types.FunctionType, weakref.ref):
    d[t] = _copy_immutable
t = getattr(types, "CodeType", None)
if t is not None:
    d[t] = _copy_immutable

d[list] = list.copy
d[dict] = dict.copy
d[set] = set.copy
d[bytearray] = bytearray.copy

if PyStringMap is not None:
    d[PyStringMap] = PyStringMap.copy


def copy(x):
    """Shallow copy operation on arbitrary Python objects.
    See the module's __doc__ string for more info.
    """
    #복사하는 Class의 Type 식별
    cls = type(x)
    
    copier = _copy_dispatch.get(cls)
    if copier:
        return copier(x)

    if issubclass(cls, type):
        # treat it as a regular class:
        return _copy_immutable(x)

    copier = getattr(cls, "__copy__", None)
    if copier is not None:
        return copier(x)

    reductor = dispatch_table.get(cls)
    if reductor is not None:
        rv = reductor(x)
    else:
        reductor = getattr(x, "__reduce_ex__", None)
        if reductor is not None:
            rv = reductor(4)
        else:
            reductor = getattr(x, "__reduce__", None)
            if reductor:
                rv = reductor()
            else:
                raise Error("un(shallow)copyable object of type %s" % cls)

    if isinstance(rv, str):
        return x
    return _reconstruct(x, None, *rv)