Re: [boost] Macros at namespace scope: trailing semicolon?

From: Rob Stewart (stewart_at_[hidden])
Date: 2005-07-14 15:53:59

From: "Arkadiy Vertleyb" <vertleyb_at_[hidden]>
> "David Abrahams" <dave_at_[hidden]> wrote
> 
> > I am defining a macro,
> >
> >   BOOST_PARAMETER_KEYWORD(tag_namespace, name)
[snip]
> > will interact more smoothly with editors and pretty-printers.  So I
> > can't see any good reason not to require the semicolon.  Arguments?
> 
> We have a similar problem in typeof, and at this point semicolon is not
> required.  This leads to all the problems with the editor that you
> mentioned, and, if the user does supply the (second) semicolon, some
> compilers emit warnings, so I am by no means happy with the situation.

Yep.

> However, if the semicolon is required, and the user doesn't supply it, the
> compiler will produce an error message, which will expose implementation
> details of this macro, and most likely be of little help.

That error message will alert the user to having misused the
macro.  A glance at the documentation will reveal that a
semicolon is required.  It really doesn't require that the user
dig into the implementation details to learn that a semicolon is
needed.

> So, the choice is actually between two evels, and I am not really sure which
> one is less evel.

I don't see it as choosing the lesser of two evils.

> Also, I think, this problem is very generic, and once it's decided which
> style is prefferrable, it may be a good idea to turn it into a guideline, so
> that it is consistent between the Boost libraries.

Agreed.

-- 
Rob Stewart                           stewart_at_[hidden]
Software Engineer                     http://www.sig.com
Susquehanna International Group, LLP  using std::disclaimer;