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Subject: Re: [boost] [c++1] BOOST_NOEXCEPT macros?
From: Domagoj Saric (domagoj.saric_at_[hidden])
Date: 2011-10-19 11:21:30

On 11.10.2011. 13:54, Beman Dawes wrote:
> On Tue, Oct 11, 2011 at 5:42 AM, Domagoj Saric
> <domagoj.saric_at_[hidden]> wrote:
>> I must I don't understand why would using the mentioned compiler specifics
>> require a different macro? AFAICT these are just different keywords that say
>> the same thing to the compiler and the user (unless someone is actually
>> worried by the fact that MSVC will not call std::unexpected/terminate in
>> case you violate the promise you made about the function in question?)
> Good question. There are two cases:
> (1) For C++03 compilers, the macro user wants the mentioned compiler
> specifics. That's the case an additional macro is needed for.
> (2) For C++03 compilers, the macro user wants nothing inserted. That's
> the case covered by the macros I've added to trunk. This case arises
> because a lot of existing code isn't decorated with either throw() or
> a compiler specific attribute, and the user doesn't want to add that
> now. In applying noexcept to the standard library, this was by far the
> most common situation encountered - there was no existing exception
> specification.
> Note that cases (1) and (2) may be interleaved in the same translation
> unit, so using a config macro to specify the behavior won't work well,
> and isn't a preferred approach anyhow.

I must say I still don't see why (1) would require an additional macro because I
don't see why (2) would be required/wanted at all..? IOW why would someone want
noexcept but not __attribute__(( nothrow ))?

ps. except, as said previously, if there is a real world person/problem that
depends on the defined std::unexpected/std::terminate behaviour of noexcept as
opposed to undefined or implementation defined behaviour of a compiler specific
in case "someone violates a promise given about the particular function"...

"What Huxley teaches is that in the age of advanced technology, spiritual
devastation is more likely to come from an enemy with a smiling face than
from one whose countenance exudes suspicion and hate."
Neil Postman

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