-----Original Message----- From: boost-bounces@lists.boost.org [mailto:boost-bounces@lists.boost.org] On Behalf Of Marcus Lindblom Sent: 18 January 2008 12:47 To: boost@lists.boost.org Subject: [boost] [review] General comment on boost::singleton I think the singleton lib is good as a boost addition, because having many different singleton implementations suck. I also think that boost should encourage good code style.
Therefore, I vote for an implementation that both separates the concepts provided (i.e. safe construction, uniqueness, global access & locking). The lib should also provide some kind of unifying scheme, so that the "classic-singleton" can be achieved by applying everything.
Also, I think some good motivational documentation on why the classic singleton is not a scalable idea would be appropriate, so that we could get users to think about the orthogonal concepts and whether they really do need all concepts in one go. (Many of us have found out that we only need a subset, after much pain....)
Like Marcus, I've also looked briefly at the docs and followed some of the discussion. I sense that singletons do have uses, despite some intemperate 'fundamentalist religious' objections. And I think a Boost singleton must be a Good Idea, even if not to everyones taste - they don't have to use it. I accept that there are at least two concepts which are presented together, but I can see why - using singletons means you probably also want value initialisation. So I conclude Marcus's suggestion has merit. I sense it would be a Bad Idea to throw the whole proposal out. Paul --- Paul A Bristow Prizet Farmhouse, Kendal, Cumbria UK LA8 8AB +44 1539561830 & SMS, Mobile +44 7714 330204 & SMS pbristow@hetp.u-net.com