Thread: Bjarne's comments about exception specification

Hello everyone,


How do you understand the Bjarne's comments about exception specification? Especially, "not required to be checked across compilation-unit" and "violations will not be caught at run time"?

section 14.6.1 Checking Exception Specifications

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Importantly, exception-specifications are not required to be checked exactly across compilation-unit boundaries. Naturally, an implementation could check. However, for many large and long-lived systems, it is important that the implementation does not -- or, if it does, than it carefully gives hard errors only where violations will not be caught at run time.
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thanks in advance,
George

Well I'm not sure exactly what he means, but I do know that exception specifications are completely useless and should be avoided whenever possible:
Chapter 75. Avoid exception specifications

Thanks cpjust,


I need to maintain some code which has exception specification, and I have to understand the concept. Looks like you are experienced at this topic, any ideas about my original question?

Originally Posted by cpjust

Well I'm not sure exactly what he means, but I do know that exception specifications are completely useless and should be avoided whenever possible:
Chapter 75. Avoid exception specifications

regards,
George

Thanks King,


What means this part?

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However, for many large and long-lived systems, it is important that the implementation does not -- or, if it does, than it carefully gives hard errors only where violations will not be caught at run time.
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Originally Posted by King Mir

It means that if exception specifications in two different compilation units disagree, that does not have to be a compile time error. It is however, undefined behavior.

regards,
George