I believe that's the STM approach, which has the advanrtage of: * can synchronize across multiple pieces of data
but has the disadvantage of: * work must be "pure" since it can be retried * possibly less efficient due to possibility of retrying In the example I posted above, I only need to: * modify a single atom and the approach I presented above: * can be impure, since it is guaranteed to only run once * is guaranteed to succeed (without retrys) On Sun, Feb 16, 2014 at 2:25 PM, Ramesh <ramesh10dul...@gmail.com> wrote: > You can use a ref instead of an atom. And use dosync with multiple alter, so > everything is safely inside a transaction. > > On Feb 16, 2014 2:04 PM, "t x" <txrev...@gmail.com> wrote: >> >> Hi John, >> >> Your solution is perfectly valid and optimal for the problem I >> described above. >> >> >> Unfortunately, I forgot to mention an additional constraint: sometimes I >> do: >> >> (let [ foo (:some-selector @data-atom) ] >> (swap! data-atom update-in [:other-selector] ... )) >> >> which the -> doesn't quite work on, but my ugly hack above does resolve. >> >> >> The problem being -- I want to update one part of the atom, but it >> depends on another part of the atom. >> >> I ended up with the following hack: >> >> (defn tswap! [atm func] >> (swap! atm >> (fn [old] >> (let [natm (atom old)] >> (func natm) >> @natm)))) >> >> >> On Sat, Feb 15, 2014 at 4:09 PM, John D. Hume <duelin.mark...@gmail.com> >> wrote: >> > On Sat, Feb 15, 2014 at 6:04 PM, t x <txrev...@gmail.com> wrote: >> >> >> >> >> >> (defn what-I-want [] >> >> (with-atom some-atom >> >> assoc-in ... >> >> assoc-in ... >> >> update-in ...)) >> > >> > >> > I often do something like this and don't find it too ugly: >> > (swap! my-atom #(-> % >> > (assoc-in [:k] v) >> > (update-in [:k2] 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 >> > --- >> > You received this message because you are subscribed to the Google >> > Groups >> > "Clojure" group. >> > To unsubscribe from this group and stop receiving emails from it, send >> > an >> > email to clojure+unsubscr...@googlegroups.com. >> > For more options, visit https://groups.google.com/groups/opt_out. >> >> -- >> 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 >> --- >> You received this message because you are subscribed to the Google Groups >> "Clojure" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to clojure+unsubscr...@googlegroups.com. >> For more options, visit https://groups.google.com/groups/opt_out. > > -- > 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 > --- > You received this message because you are subscribed to the Google Groups > "Clojure" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to clojure+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. -- 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 --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
