Question

see the code below:

public static int Main()
{
    int j = 20;
    for (int i=0; i < 10; i++)
    {
        int j = 30;    //can't do this
        Console.WriteLine(j + i);
    }
    return 0;
}

An error occurs in C#, because here it does not do variable hiding & gives error :

A local variable named ‘j’ cannot be declared in this scope because it would give a different meaning to ‘j’ which is already used in ‘parent or current’ scope.

if we run above program in c++, it works, in c++ it supports variable hiding in this situation.

Now my question is that , what is the reason behind this?
why C# developer decided to not support to hiding here.?
why C++ allow hiding here?

Answer 1

C++ kept things like this for compatibility with C. This was allowed in C, so it’s allowed in C++.

C# doesn’t have nor need compatibility. So this “hiding” was weeded out.