Unfortunately, no, but not from lack of trying. The best lead I've got thus far is that there is a disj call that returns a defective set, which returns a positive value for count, but does not seem to contain any elements.
I've tried to capture the offending values, but I can't reproduce the bug with them. I can't arrange the elements of the set to be in the same order, and I can't get the same hash values for the maps (which contain js objects). I suspect the issue may have something to do with hash collisions. The app state is being shuffled with some randomness, and the problem arises consistently after a minute or two of churn. If I add an extra "artificial" hash field to each element stored in the set, then the problem disappears (or perhaps it is postponed). I noticed that the defective sets always contain many elements with the same hash. (I know very little about how sets and hashing are implemented.) I'll keep debugging. - austin On Tuesday, May 20, 2014 8:36:37 AM UTC-7, David Nolen wrote: > > Can you demonstrate a complete minimal example? > > Thanks, > David > > > On Tue, May 20, 2014 at 4:06 AM, Austin Haas > <aus...@pettomato.com<javascript:> > > wrote: > >> I'm having trouble isolating a small test case. I call the following code >> in an update tick: >> >> (let [prev' @prev >> state' @state] >> (let [rems (clojure.set/difference prev' state') >> adds (clojure.set/difference state' prev')] >> (reset! prev state') >> (assert (= (count rems) (count (set rems)))))) >> >> (prev and state hold sets of maps.) >> >> After running for a few minutes, the assert will fail. The 'rems' and >> 'adds' will report that their count is > 1, but when I try to access the >> elements there are either none or only one. >> >> What would cause a set to return an incorrect value for count? >> >> FWIW, the elements of the sets are maps, and one of the fields holds a >> mutable javascript array. That was my first suspicion, but the array isn't >> mutated in my code, and I use a memoized function to generate it (to >> preserve identity). >> >> I'm using [org.clojure/clojurescript "0.0-2202"]. >> >> -- >> You received this message because you are subscribed to the Google >> Groups "Clojure" group. >> To post to this group, send email to clo...@googlegroups.com<javascript:> >> Note that posts from new members are moderated - please be patient with >> your first post. >> To unsubscribe from this group, send email to >> clojure+u...@googlegroups.com <javascript:> >> 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+u...@googlegroups.com <javascript:>. >> For more options, visit https://groups.google.com/d/optout. >> > > -- 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/d/optout.
