Re: [boost] [system] error report refinement

From: Guillaume Melquiond (guillaume.melquiond_at_[hidden])
Date: 2006-08-28 11:10:06

Le lundi 28 août 2006 à 09:49 -0400, Beman Dawes a écrit :
>    extern error_code throw_on_error;
> 
> Then only a single signature is required:
> 
>    whatever foo( error_code & ec = throw_on_error );
> 
> On an error, the implementation of foo throws if ec != &throw_on_error, 
> otherwise it sets ec to the appropriate error_code and returns without 
> throwing.

I often use this idiom and I like it.

You may however encounter problems on systems that have difficulties
mixing static and shared libraries. It may be safer to stick with this
version of the idiom:

whatever foo(error_code *ec = NULL);

Best regards,

Guillaume