How the operator ^ is used in C++

Question

I understand in C , the operator ^is used for bit-wise EX-OR. In one of the C++ code I saw the following lines where this operator is used:

 using namespace System::Threading;
 public ref class Expert : public System::Windows::Forms::Form
{
    int i ;
        float a ;


public:
    int count;
    Thread^ th;

     }

What is the meaning of ^ here ?

That isn't C++, it's C++/CLI which is a Microsoft extension of C++. — john, Nov 16 '12 at 12:56
It means that the code isn't C++, but a somewhat similar language from Microsoft. (I forget the name of the language, but it has C++ in it.) — James Kanze, Nov 16 '12 at 12:56
In C++ (as in C) it is the bitwise exclusive-or (XOR) operator. In the context of your question, it is something completely different and not C++. — juanchopanza, Nov 16 '12 at 13:06

score 5 · Answer 1 · answered Nov 16 '12 at 12:58

5

That is not C++, it's a variant of C++ named C++/CLI and is a Microsoft extension to make managed .NET applications in C++.

The ^ when used like that is do denote managed pointers, i.e. memory that can be garbage collected.

answered Nov 16 '12 at 12:58

Some programmer dude

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Just for clarification I am asking: do I need to use free() , to release such a memory ? – gpuguy Nov 17 '12 at 07:15
@gpuguy No, it can only be allocated with `gcnew` and will be free'd automatically. It's like creating new objects in C#. – Some programmer dude Nov 17 '12 at 07:29

score 3 · Answer 2 · answered Nov 16 '12 at 12:56

3

That's a .net reference type, in C++/CLI! That is, Expert::th is a reference to an instance of System.Threading.Thread (or null). You can also tell it's C++/CLI by the fact it's inheriting from a .net class.

answered Nov 16 '12 at 12:56

Adam Wright

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score 3 · Answer 3 · answered Nov 16 '12 at 12:56

3

That's not C++, that's C++/CLI. The ^ stands for "handle" and is like a managed pointer.

answered Nov 16 '12 at 12:56

Kos

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score 3 · Answer 4 · answered Nov 16 '12 at 12:57

You will also see the ^ ("hat") symbol in C++/CX, which is C++ with a set of extensions that helps support Windows 8 (WinRT) development.

http://en.wikipedia.org/wiki/C%2B%2B/CX

http://en.wikipedia.org/wiki/WinRT#C.2B.2B_.28WRL.2C_Component_Extensions.29

How the operator ^ is used in C++

4 Answers4