Re: [boost] [review] **NEXT WEEK** Review of Outcome (starts Fri-19-May)

Subject: Re: [boost] [review] **NEXT WEEK** Review of Outcome (starts Fri-19-May)
From: charleyb123 . (charleyb123_at_[hidden])
Date: 2017-05-15 00:39:28

>
> spaketh Vinnie:
>
<snip>,

Head check: Is the following function signature "correct" or should it
> use system_error?
>
>     template<
>         typename SyncReadStream,
>         typename MutableBufferSequence>
>     std::size_t
>     read(
>         SyncReadStream& s,
>         MutableBufferSequence const& buffers,
>         boost::system::error_code& ec);
>

That signature is "correct":

(a) It happens to use 'boost::system::error_code', which is a complete
C++03 implementation compatible with C++11's <system_error>.

(b) C++11 libraries can consider moving to 'std::error_code'.  Otherwise,
an "adapter" can be implemented to enable 'boost::system::error_code' to
inter-operate with C++11's 'std::error_code'. A nice blog article by Bjorn
Reese on that topic can be found at:
http://breese.github.io/2016/06/18/unifying-error-codes.html

(c) The C++11 'class std::system_error : public std::runtime_error { ...};'
is a convenience utility to 'throw' a 'std::error_code' value as
"payload".  Since your 'read()' function signature (by convention) appears
to be non-throwing, you wouldn't need 'std::system_error' here (as the
'std::error_code' can be populated directly in the function body).

Hope that helps ...?

--charley