Thanks Steve and Cosmin! I understand it now. On Tue, Jan 20, 2009 at 4:53 PM, Stephen C. Gilardi <squee...@mac.com> wrote: > > On Jan 20, 2009, at 5:32 PM, Mark Volkmann wrote: > >>> Here's one: >>> >>> (defn read-my-file [] >>> (with-open [reader (BufferedReader. (FileReader. "my-file.txt"))] >>> (doall (line-seq reader)))) >>> >>> "line-seq" returns a lazy sequence, but you have to consume that >>> sequence before "with-open" closes the file. >> >> How is it different if you change "doall" to "dorun"? According to >> their doc strings, they both "can be used to force any effects. Walks >> through the successive rests of the seq" > > Using doall will cause read-my-file to return a seq of all the lines. dorun > will return nil. > > Here's a simpler example: > > user=> (doall (map #(do (prn %) %) [1 2 3])) > 1 > 2 > 3 > (1 2 3) > user=> (dorun (map #(do (prn %) %) [1 2 3])) > 1 > 2 > 3 > nil > user=> > > (Note the difference in return value.) > > --Steve > >
-- R. Mark Volkmann Object Computing, 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 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 -~----------~----~----~----~------~----~------~--~---
