I think this is an example of locals-clearing at work: https://groups.google.com/forum/#!topic/clojure/FLrtjyYJdRU
My guess is that the compiler clears the references 'at the point of last reference', but in this case s2 has no last reference. On Fri, Apr 1, 2016 at 9:07 AM John Jacobsen <eigenhom...@gmail.com> wrote: > The problem of correctly handling large lazy sequences so they don't blow > up in memory came up at work this week. > > I thought I would try to explain the following simple case to our Monday > afternoon study group, and I realized I don't understand it 100%: > > (def n 1e8) > > (let [s1 (range n) > s2 (map identity s1)] > (count s2)) > > ;;=> 100000000 > > > (let [s1 (range n) > s2 (map identity s1)] > (count s1)) > > ;;=> GC overhead limit exceeded > > For the first case, I get that in consuming s2, elements of both s1 and s2 > are consumed and garbage-collected; and that in the second case, clearly s1 > can't be released as it's consumed because s2 might still need it (even > though we never realize s2). My question is, as s1 is consumed in the > second case, how does it "know" that s2 still holds a reference to it, and > that it therefore should keep the realized values? What is the relevant > difference between these two examples? And where in the Clojure/core code > are the relevant details? > > Thanks in advance! > John > > -- > 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. > -- 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.
