After reading [https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p2688r5.html ], I have a few questions I’d like to get clarified.

First, there is no regex (regular expression) matching, as match is a supperset of switch. For example:

string str = "";

str match
{

    case /^http:\/\/.+/:

        f1(); 

        break;

   case /^tcp:\/\/.+/: 

        f2(); 

        break;

    default:

        break;

}

Then, in what scenarios can matching tuples be used?  Can switch be used as a replacement in this scenarios?

Next，How to Handle Multiple Type Operators When Matching Variants? For example：

class X

{

operator int(){return  0;}

operator std::string() { return ""; }

};

X x;

x match {

int: let i => printf("%d", i);

std::string : let str => printf("%s", str.c_str());

}

Finally, when matching nested structures:

using Command = variant<Quit, Move, Write, ChangeColor>;

int DoCommand(Command& cmd);

Command& GetCommand();

If GetCommand is a function from a third-party library, how can my program determine which specific Command type is returned?

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