Re: [boost] [review] Review of Outcome v2 (Fri-19-Jan to Sun-28-Jan, 2018)

Subject: Re: [boost] [review] Review of Outcome v2 (Fri-19-Jan to Sun-28-Jan, 2018)
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2018-02-01 00:02:17

On 02/01/18 01:26, Vinícius dos Santos Oliveira via Boost wrote:
> 
> How pushing a "I forgot to do proper error handling" to compile time errors
> becomes "this is just axiomatic belief and helps no-one"?
> 
> During this same review, Andrzej Krzemienski noted an improper exceptions
> handling of exceptions in the swap function:
> 
> Also, it is possible that while reswapping, another exception will be
>> thrown. In general, you cannot guarantee the roll-back, so maybe it would
>> be cleaner for everyone if you just declared that upon throw from swap, one
>> cannot rely on the state of `result`: it should be reset or destroyed.
> 
> Should we remember the variant saga maybe[1][2]? These are not isolated
> cases. They keep happening.

It's not the exceptions that made variant difficult. It's *the 
possibility of a failure* at certain points in some cases. You would 
have the same difficulty defining behavior in these cases with any error 
reporting mechanism, exceptions or not.