Very simple but petentially usefull.

Add two methods to std::exception

int line();            // returns line that exception was thrown from.
std::string file(); // returns file that exception was thrown from.

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Thaddeus L Olczyk wrote:

>
> int line();            // returns line that exception was thrown from.
> std::string file(); // returns file that exception was thrown from.

And what makes you think the compiler knows this?  You're introducing a LOT
of overhead.  In addition to what ever the user explicitly throws, the implementation
must carry around file and line for you.  This is a lot of overhead that if you need
you can easily do yourself.


#define LINE_EXCEPTION LineException(__FILE__, __LINE__)

struct LineException {
    string file;
    int    line;
    LineException(string f, int l) : file(f), line(l) { }
};


 try {
     throw LINE_EXCEPTION;
 } catch(LineException& le) {
    cout << "Exception thrown from " << le.file << ":" << le.line << endl;
 }

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You are right that this could be very useful for debugging exceptions.
However, it would conflict with one of the basic design criteria for C++:

The zero-overhead rule: "What you don't use, you don't pay for."

It would probably be a better idea to have the compiler emit some
exception-tracking code into the compiled program. (And of course, this
should be an optional behaviour!)

-- Per Velschow



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