A doubt regarding inheritance

[subith86]

Hi friends,

I was trying out some inheritance related stuff and found something. I just want to know the reason why.

I have a ParentClass and a ChildClass. Both have an integer named commonVar1. Also both have a getter method of the same name. Here goes the code.

class ParentClassOT
{
    public:
        ParentClassOT();
        ~ParentClassOT();
        int commonVar1;
        int GetcommonVar1() { return commonVar1; }
};

class ChildClassOT : public ParentClassOT
{
    public:
        ChildClassOT();
        ~ChildClassOT();
        int commonVar1;
        int GetcommonVar1() { return commonVar1; }
};

In my main method I'm doing something like this

ChildClassOT obj1;
cout<<obj1.GetcommonVar1();

Now I'll give out the results of different combinations I have tried
1. Code as it is : outputs garbage
2. Parent getter (line 7) commented : outputs garbage
3. Child member variable (line 6) commented : outputs garbage
4. Child getter (line 7) commented : outputs -1
5. Child getter and member variable commented : outputs garbage

I'm okay with results 1,2,3 and 5. But I don't get why 4th one gives a -1.
Could somebody please help... :confused:

[chiwawa10]

Is that all the codes that you have? Did you ever set any value to your variable 'commonVar1' before calling GetcommonVar1() method? If not, I suppose the result would be unexpected and the -1 is only a coincidence.

If I'm not wrong, the child's property 'commonVar1' takes precedence over the parent's. Anyway as a side note, I don't see any reason why you should declare a variable in the child class having the same name as the parent's.

[subith86]

Did you ever set any value to your variable 'commonVar1' before calling GetcommonVar1() method?

there is no setter method. I intentionally did it like this to see a garbage value.

I don't see any reason why you should declare a variable in the child class having the same name as the parent's.

yes I know. This is not a professionally written code. I was learning inheritance and was trying out different combinations.

If it's a coincidence then i'll have to check with other compiler. But i feel this is not a coincidence.

[mrnutty]

-1 is still garbage

[subith86]

Did you ever set any value to your variable 'commonVar1' before calling GetcommonVar1() method?

there is no setter method. I intentionally did it like this to see a garbage value.

I don't see any reason why you should declare a variable in the child class having the same name as the parent's.

yes I know. This is not a professionally written code. I was learning inheritance and was trying out different combinations.

If it's a coincidence then i'll have to check with other compiler. But i feel this is not a coincidence.

[template<>]

If you don’t initialize your variables, you will get garbage...
garbage in this case is any value that int is capable of representing...