future also uses the same threadpool as agents, so once you call future the threadpool spins up, and just sort of sits around for a while before the jvm decides to exit, which is why the program would sit around for 50 seconds
On Wed, Nov 25, 2009 at 10:30 AM, Hong Jiang <h...@hjiang.net> wrote: > Thanks for your replies David and Sean. Yes, I made a mistake thinking > that future takes a function and its arguments, so the function was > never called in my program. > > On Nov 25, 8:21 am, David Brown <cloj...@davidb.org> wrote: >> On Tue, Nov 24, 2009 at 09:04:38PM -0800, Hong Jiang wrote: >> >Hi all, >> >> >I'm new to Clojure and playing with small programs. Today I wrote a >> >snippet to figure out how future works: >> >> >(defn testf [] >> > (let [f (future #(do >> > (Thread/sleep 5000) >> > %) >> > 5) >> > g 7] >> > (+ g @f))) >> >> You don't ever evaluate the function containing the sleep, you just >> create it, and then immediately return 5. >> >> Future contains an explicit do, so you can just do the steps in the >> future: >> >> [f (future >> (Thread/sleep 5000) >> 5) >> ... >> >> Or, if you want to get the function call in, you'll need to call it: >> >> [f (future (#(do (Thread/sleep 5000) %) 5)) ...] >> >> David > > -- > 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 -- And what is good, Phaedrus, And what is not good— Need we ask anyone to tell us these things? -- 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
