Re: [boost] Proposed Boost Assert -- once again

From: Kevin S. Van Horn (Kevin.VanHorn_at_[hidden])
Date: 2002-11-12 12:26:54

Vladimir Prus writes:

> 1. I'd prefer to have BOOST_NDEBUG instead of BOOST_DEBUG, for
> consistency with NDEBUG. I simply want BOOST_ASSERT to work for
> debug builds. Or doesBOOST_DEBUG have non-empty initial value?

Yes, that was my original choice.  I changed it to BOOST_DEBUG for two 
reasons:

1. That's the way it was in the existing (undocumented) 
<boost/assert.hpp>.

2. Experienced C/C++ programmers already know to define NDEBUG for 
optimized code, but unless they read the documentation for Boost Assert, 
they won't know to define BOOST_NDEBUG.  Now consider someone who is just 
using one of the Boost libraries, but not Boost Assert.  If that library 
uses Boost Assert (as it should), it will take a performance hit when 
BOOST_NDEBUG is not defined.  The user won't know why this is happening, 
as he will have had no reason to read the Boost Assert documentation.

I suppose one option would be to have a READ THIS FIRST section in the 
documentation, that users should read regardless of which library(ies) 
they intend to use.

> 2. failed_exception can be safely derived from std::exception. Unlike
>    std::logic_error, it does not use std::string.

Good point.

> 3. Docs for BOOST_ASSERT say
>   'Otherwise, if user has already provided a definition for BOOST_ASSERT,
>    the definition is left unchanged.
>
>   Is this accurate? If user has provided its own definition for BOOST_ASSERT,
>   then calling the BOOST_ASSERT macro will do what user coded. You must
>   mean that if there's BOOST_ASSERT defined then <boost/assert.hpp> won't
>   change that definition.

That's what I thought I said.  I guess my wording was unclear.