Thanks very much Cedric. (What do you mean by: 'Clearly "board" is a chunked seq in this case.'?)
On Monday, November 25, 2013 1:58:36 PM UTC, Cedric Greevey wrote: > > Clearly "board" is a chunked seq in this case. > > Use doseq when you want side effects for-each of some seqable, but don't > care about the return values. The arguments for doseq are identical to > those for for, but a) doseq will return nil and b) if the output of for was > discarded (rather than the repl realizing the sequence to print the nils) > the side effects would never take place, whereas doseq forces them to take > place whether or not the nil *it* returns is used or discarded. > > > On Mon, Nov 25, 2013 at 8:25 AM, Ambrose Bonnaire-Sergeant < > abonnair...@gmail.com <javascript:>> wrote: > >> Hi Edward, >> >> I believe the return value of your expression is (nil nil nil nil ...), >> but the printlns are forced just after the ( is printed. >> >> Thanks, >> Ambrose >> >> >> On Mon, Nov 25, 2013 at 9:14 PM, <edw...@kenworthy.info <javascript:>>wrote: >> >>> Some (println) weirdness (board is a vector to vectors): >>> >>> (println (board 0)) >>> (println (board 1)) >>> (println (board 2)) >>> (println (board 3)) >>> (println (board 4)) >>> (println (board 5)) >>> (println (board 6)) >>> (println (board 7)) >>> >>> Works as I would expect, printing to the console. >>> >>> However: >>> >>> (for [row board] >>> (println row)) >>> >>> Doesn't: the output from println is part of the result of evaluating the >>> for (along with a slew of nils). >>> >>> ([:empty :empty :empty :empty :empty :empty :empty :empty] >>> [:empty :empty :empty :empty :empty :empty :empty :empty] >>> [:empty :empty :empty :empty :empty :empty :empty :empty] >>> [:empty :empty :empty :white :black :empty :empty :empty] >>> [:empty :empty :empty :black :white :empty :empty :empty] >>> [:empty :empty :empty :empty :empty :empty :empty :empty] >>> [:empty :empty :empty :empty :empty :empty :empty :empty] >>> [:empty :empty :empty :empty :empty :empty :empty :empty] >>> nil nil nil nil nil nil nil nil) >>> >>> Any idea why there is any difference at all between the two? The only >>> thing I can think of is for's lazy evaluation but I don't see how. >>> >>> -- >>> -- >>> 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/groups/opt_out. >>> >> >> -- >> -- >> 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/groups/opt_out. >> > > -- -- 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/groups/opt_out.
