On extension headers and ease of use

[Wu Yongwei]

Hi gurus and folks here,

I am a user of GCC but new to this mailing list.  More and more I build
programs on GCC 3 instead of the older 2.95, and I have found the
different file names and namespace for the "extensions" like slist and
so on.  I searched on Google and found it done quite some time ago, but
I have no clue why it must be done.  Hence this posting.

OK, I know that they do not belong to namespace std.  But the current
solution seems to me worse than non-conformance.  For I now must use an
unwieldy artificial construct (GCC 3/Libstdc++ is not the only
compiler/library on this planet, isn't it?) to use slist, like:

#if !defined(HAS_STLPORT) && defined(__GNUC__) && __GNUC__ == 3
#include <ext/slist>
using __gnu_cxx::slist;
#else
#include <slist>
using std::slist;
#endif

And consider the possibility if one day slist is standardized into the
std namespace (anyone knows for sure that it won't?).  How would
libstdc++ be?  Reverting back to the old behaviour?  What a mess!

Open source software often pays a lot of attention on standards.  Surely
it is not a bad thing, but I want to emphasize that ease of use
(portability, backward compatibility, etc.) is often as equally
important.  I fail to see the virtue of this change because it makes
life worse for cross-platform development.

Maybe I missed something important.  If so, please correct and enlighten me.

Thanks.

Wu Yongwei