You can not extend them, as they are marked final. Another point to consider is clojure-in-clojure. If that is ever going to happen, one needs to be able to implement Atom as well. It is also generally better to code to an interface rather than to an implementation.
Alter and send also work differently from swap!, so I think it makes sense to have separate functions for them. But CouchDB also exhibits shared, synchronous, independent state, so I don't see the point in prohibiting the use of the same interface. On Dec 6, 11:24 am, Benjamin Teuber <bsteu...@googlemail.com> wrote: > I guess it was Rich's intention to have swap! be used for real atoms > only so your code remains understandable - that's why it's called > swap! for atoms, alter for refs and alter-var-root for vars. > > So why not define your own protocol for updating documents? If you > really want (usually bad idea, I guess) you could still extend atoms > or even refs to support this protocol, too. > > Regards, > Benjamin > > On 5 Dez., 23:29, Pepijn de Vos <pepijnde...@gmail.com> wrote: > > > > > > > > > tl;dr: Please add an interface to clojure.lang.Atom. kthxbye > > > I had the brilliant idea of using CouchDB for something equally brilliant, > > and if possible implement a Clojure view server. Turns out Clutch fits the > > bill perfectly, except that I would like to use Aleph, and Couch is using > > something called MVCC. > > > I haven't looked into the libs to deep, but I know the REST API, and what > > it does for updating is that you need to supply the current revision and if > > it doesn't match (i.e. there has been another update), the update fails. So > > then you need to get the new _rev and try again. Much the same way > > compare-and-set! works. > > > I thought it would be perfect to implement IAtom and IDeref to get the > > latest value and to swap! documents in a spin loop with a side-effect-free > > function, like atoms do. > > > But it turns out there is no interface for Atom and it is marked final. The > > same is true for Ref and Agent, but raek suggested this might be because > > they are more complex and integrated with the STM. > > > Is there a good reason why I'm not allowed to implement my own atom? If > > not, can it be added? Thanks. > > > Groeten, > > Pepijn de Vos > > -- > > Sent from my iPod Shufflehttp://pepijndevos.nl -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
