export gone, exception specs deprecated. Will this affect your code?
This latest Herb Sutter trip report on the C++0x standardisation process indicates that the committee has decided to completely drop the "export" concept for templates, and to deprecate exception specifications.
I think these are both good moves, but I'm interested if anyone out there has a code base where these changes will cause them sleepless nights?
I've been programming in C++ since cfront 1.0, and I am happy to say I've never written an exception specification or allowed one in code that I was responsible for. When they were proposed, I called Bjarne Stroustrup on the phone and cried, "Don't do it!" I gave all the reasons why they were a horrible idea. To my surprise, he said something like, "I know." When I asked why the feature-from-Hades was going into the spec, he said there was a Big Player whose "experts" resolutely insisted that it had to go into the spec or they would absolutely not sign off, period, end of discussion. If I ever knew who it was, I've forgotten.
I've been deprecating a long time. :-)
Certainly no sleepless nights on any of the codebases I have been involved with over the past 5-6 years. I don't think I've ever encountered anybody who used export , plus experts like Herb Sutter have been railing against exception specifications (apart from nothrow) for so long that most programmers have got the message by now.
export was never implemented properly in gcc or MSVC, (but apparently was so in EDG/Comeau, as comments say), but I'd guess it never got widespread acceptance. (But I mainly live in the gcc/msvc world, so my viewpoint doesn't encompass the entire C++ community.)
As for exception specs, I believe they were broken too.
Third, deprecation doesn't mean will-cause-compiler-errors. It's just strongly suggested that user shouldn't use it and, if applicable (not so much here, I think), move on to other mechanisms to achieve the same goal.
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