Re: [boost] Boost debug facilities

From: David Abrahams (dave_at_[hidden])
Date: 2002-11-03 13:11:03

Hi Kevin,

I support the direction you're going in.

-Dave

"Kevin S. Van Horn" <Kevin.VanHorn_at_[hidden]> writes:

> A few months ago there was some talk about checking preconditions.  In 
> some places in the Boost libraries, exceptions are thrown, and in others, 
> assert() or its equivalent is used.  I mentioned that you generally want 
> to core dump when you're debugging, but in many enterprise settings this 
> is not acceptable for production code, and it is preferable to throw an 
> exception (e.g., abort a single transaction).  What you really want is to 
> allow the user to choose which behavior you get.
> 
> If it does not already exist somewhere in the Boost internals, and nobody 
> else is already working on it, I propose to contribute a small debug 
> library to Boost.  The intent is that this library both be used internally 
> to Boost and also made available to Boost users.  Here are the essentials:
> 
> 1. There are macros BOOST_DBG_ASSERT(e) and BOOST_DBG_ASSERT_MSG(e, msg).
> These check that e is true, and either cause an abort or an exception 
> throw if e is false.  The second form allows one to give additional 
> explanatory information if e is false.
> 
> 2. If BOOST_NDEBUG is defined, then both of the above two macros are 
> no-ops.
> 
> 3. If BOOST_NDEBUG is not defined but BOOST_DEBUG_THROW is defined, then
> the DB_ASSERT macros throw an exception containing the test expression, 
> file number, line number, and (optional) explanatory message.
> 
> Over time I expect that additional debug facilities would be added to this 
> library, in response to user input.  For example, I think it would be useful
> to have facilities that make it easy to define checked iterators such as exist
> in STLport's debug mode.  However, I think it best to start with the 
> smallest useful unit of functionality.
> 
> I also would like to get more familiar with the Boost internals, and as I 
> review the code for various libraries I expect to be submitting patches /
> enhancements that make use of the new debug facilities.
> 
> Comments?

-- 
                    David Abrahams
dave_at_[hidden] * http://www.boost-consulting.com