What is the "^" symbol in C++?

Question

Has a new symbol joined the C++ language specification while I was sleeping under a rock?

I just encountered the following question:

Restrict Text Box to only accept 10 digit number

Which suggests that the '^' symbol is somehow part of C++ (not in the legacy meaning of a bitwise-XOR)

Is this so?

If so, what does it mean? (I tried to google the question but Google didn't come up with satisfactory answers)

Solution 1

In C++ the “^” symbol is the bitwise exclusive or (xor) operator. For a single bit you have 0 ^ 0 = 1 ^ 1 = 0 and 0 ^ 1 = 1 ^ 0 = 1.

However, in the question you are refering to it is part of Microsoft special syntax for C++ development on the .NET platform known as C++/CLI or It Just Works.

Memory on .NET is garbage collected and references to objects will have to be tracked. This makes it impossible to reference these objects using a normal C++ pointer. Microsoft has decided to reuse the “^” symbol to declare a variable somewhat similar to a pointer that can reference an object on the managed heap.

^ (Handle to Object on Managed Heap)

Solution 2

In Visual C++, ^ represents a handle to a managed object. Essentially what in C# would be a reference. Allocate them with gcnew instead of new, and they will be garbage collected for you. This is how Visual C++ interacts with the CLI.

Solution 3

In the referenced answer, it's not part of the standard C++ language, it's part of the C++/CLI language that Microsoft cobbled together for .NET interop. In that language, ^ means a "pointer to managed memory."

Solution 4

The '^' syntax refers to a tracking reference in C++/CLI, a Microsoft extension to C++ which enables interaction with managed code.

Solution 5

It's not part of Standard C++. It's part of Managed C++ (Microsoft's language much like C++ for .NET). It means "a reference to ----" in much the same way a "*" means "A pointer to -----" is Standard C++.

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