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layer8yesterday at 4:13 PM1 replyview on HN

What I’m thinking of is that the C++ exception runtime would attach exceptions from destructors to any in-flight exception, forming an exception tree, instead of calling std::terminate. (And also provide an API to access that tree.) C++ already has to handle a potentially unlimited amount of simultaneous in-flight exceptions (nested destructor calls), so from a resource perspective having such a tree isn’t a completely new quality. In case of resource exhaustion, the latest exception to be attached can be replaced by a statically allocated resources_exhausted exception. Callbacks like the old std::unexpected could be added to customize the behavior.

The mechanism in Java I was alluding to is really the Throwable::addSuppressed method; it isn’t tied to the use of a try-block. Since Java doesn’t have destructors, it’s just that the try-with-resources statement is the canonical example of taking advantage of that mechanism.


Replies

pjmlpyesterday at 8:03 PM

I see, however I don't envision many folks on WG21 votting that in.