I thought up an interesting issue the other night. If you map a function over a seq of refs, then change the refs & look at the map return value (which will convert it from lazy to ...? Hmm, what's the word - motivated?) then you will get the current value of the refs.
The example code is (def refs (into [] (map #(ref %) (range 10)))) (def dref (map deref refs)) (doseq r refs (dosync (commute r #(* 2 %)))) (println dref) When you consider how map works, this actually makes total sense. However, I think that it is something of a gotcha. Normally you don't need to know that map returns a lazy seq, because normally you would be mapping over immutable data. But if you happen to map over seqs that have refs, then you might have problems. I find it conceptually jarring - normally laziness is a transparent abstraction. I guess the main reason I'm posting this is to point out the issue. I wonder if this gotcha should be highlighted somewhere in the official documentation, or am I making a mountain out of a molehill? Cheers, Brad --~--~---------~--~----~------------~-------~--~----~ 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 To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/clojure?hl=en -~----------~----~----~----~------~----~------~--~---
