🚀 go-pugleaf

The text from the DWP, as quoted by David Chase below, is actually completely
unclear as to whether an exception thrown during processing of a prior
exception causes program termination.

> John Max Skaller <maxtal@suphys.physics.su.oz.au> () writes:
>> For example you should be able to throw an exception INSIDE the body of a
>> destructor and catch it, pre-empting the execution of the rest of the body,
>> but then continuing unwinding for the first exception which triggered
>> destruction in the first place.

chase@centerline.com (David Chase) writes:
> I would hope that this is the intent of the committee.[...]  Looking at the
> April draft, I believe that this is the intent of the committee, and that
> the April draft supports it.  See [except.terminate]
> 
>   "In the following situations, exception handling must be abandoned...
>    ...
>    -- when an attempt by the implementation to destroy an object during
>       stack unwinding [1] exits [2] using an exception"
> 
> [1] Stack unwinding is defined to be the destruction of objects constructed
> on the path from a try block to the throw-expression.
> 
> [2] "exits" is the crucial word -- a destructor which throws an exception
> but does not propagate it to the destructor's caller, is not using the
> exception to exit.

The part of this text that makes it incomprehensible is the undefined
terminology, "when an *attempt* exits..."  What is an "attempt"?  Do they
mean:
- "when any *function* exits using an exception"?
- "when *any* *block* of code is exited by means of a `throw' statement"?
- "when the *destructor* of an object that was on the stack when the prior
  exception was thrown exits with an exception"?

No, I don't want someone to tell me their personal interpretation.  I want the
committee to revise text of the draft to use unambiguous, *well-defined*
terminology.


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