Re: [boost] [any] boost::get style accessors

Subject: Re: [boost] [any] boost::get style accessors
From: Christoph Heindl (christoph.heindl_at_[hidden])
Date: 2010-04-29 11:50:59

On Thu, Apr 29, 2010 at 1:10 PM, Stewart, Robert <Robert.Stewart_at_[hidden]> wrote:
> Christoph Heindl wrote:
>> On Wed, Apr 28, 2010 at 8:00 PM, Stewart, Robert
>> <Robert.Stewart_at_[hidden]> wrote:
>>
>> > At that point, I think they should be on par with any_cast
>> > rather than built on any_cast so that exceptions needn't be
>> > translated.  Exception handling overhead is too costly to do
>> > it twice when it isn't necessary.
>>
>> I agree. I don't see any added value by using bad_get, except all
>> boost:get accessors would throw bad_get exceptions.
>
> Perhaps you missed my point.  I was suggesting that your gets be implemented at the same level of access as any_cast so no exception translation were needed.  In other words, take code straight from any_cast and use it to implement get, provided bad_cast is deemed useful.

Indeed I did. In boost 1.42 this corresponds to duplicating ~40 lines
of code to exchange the type of exception thrown. I'm not too keen of
doing this (not talking about the tests I would have to duplicate too)
:) Of course, code could be refactored to refer to a common set of
methods that take the exception to throw as templated argument, if
desired.

Best Regards,
Christoph