The doc for commute says "At the commit point of the transaction, sets the value of ref to be: (apply fun most-recently-committed-value-of-ref args)".
Looking at the source code in LockingTransaction.java, that doesn't seem to always be the case. I see this: f.fn.applyTo(RT.cons(vals.get(ref), f.args)) vals is a HashMap of in-transaction values, not most recently committed values. Inside a transaction, Refs get in-transaction values if you do a ref-set or alter on them. Within a transaction you can ref-set or alter a Ref and then do a commute on the same Ref. You can't reverse the order. Once you do a commute on a Ref, you can't do a ref-set or alter on it in the same transaction. During transaction commit and immediately before the commute functions for the Ref are called, it determines whether the Ref has an in-transaction value, meaning that ref-set or alter was called on it. If it does not then the most recently committed value for the Ref is used for the in-transaction value. So I think it is only partially true to say that when commute functions are rerun during a commit, they use the most recently committed values of Refs. That only happens if ref-set and alter were not used on the Ref before the call to commute. Am I understanding this correctly? -- R. Mark Volkmann Object Computing, Inc. --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
