Re: Structured exception information

Stephen Leake wrote:

How can I pass some error information from the constructor function
out, so that it's used when the exception is handled?

Why do you want to?

So that the handler has more information about the error?

Generally, all you can do is report the error to
the user.

That's what I want to do.

Can you give a detailed example of passing more complex information
that is actually used?

Imagine a constructor function that calls a database or a script engine with the query/script provided as a parameter. Some error can result and I want to raise an exception. The handler might benefit (even if for the purpose of presenting a nice error pop-up message) from:

- error code
- error message
- line number
- character position
- hint from the engine
- timestamp from within the engine
- ...

Another example - imagine that your compiler just prints "COMPILER_ERROR" instead of everything that it actually prints.
That wouldn't be very funny!

--
Maciej Sobczak : http://www.msobczak.com/
Programming : http://www.msobczak.com/prog/
.

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