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

From: David Abrahams (dave_at_[hidden])
Date: 2005-07-15 09:20:06

Chris Uzdavinis <chris_at_[hidden]> writes:

> However, I'd call this a poorly designed macro because it's
> misleading and error prone.  My personal guidelines are:
>
> 1) when a macro is logically its own statement, then the user should
>    provide the semicolon to aide in readability.  This makes it clear
>    that the macro is "done".  Therefore, I'd write SOME_MACRO1 to have
>    the user provide the semicolon.  This requires that the macro
>    actually be done and its effect doesn't spill into the following
>    code. 
>
> 2) when a macro is intended to modify the code that follows it, then
>    it should not have visible trailing semicolons or they will mislead
>    the user.  It should be obvious from indentation that the macro is
>    being applied as a prefix to the code that follows, rather than a
>    self-contained statement.

I like your guidelines, but I think your language is a little
problematic, and might reflect the thinking that Paul objects to.
IOW, a macro is not a statement.  Instead, a macro expansion might
_generate_ a statement.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com