Aha! I Googled for scan in seq-utils and didn't find anything. It would be nice if people stuck to standard terminology that has a continuous history going back to the early 60s.
-Per On Sat, Mar 20, 2010 at 9:40 PM, Steve Purcell <st...@sanityinc.com> wrote: > Which looks the same as clojure.contrib.seq/reductions to me... > > -Steve > > > On 20 Mar 2010, at 13:54, Per Vognsen wrote: > >> Learn to love scan: http://gist.github.com/338682 >> >> -Per >> >> On Sat, Mar 20, 2010 at 12:13 PM, Douglas Philips <d...@mac.com> wrote: >>> Hello all, >>> I'm new to clojure, but not lisp. >>> I'm looking for a functional way to index/number only some items of a >>> list. >>> >>> For example, I know I can do this (indexed is from the contrib seq_utils >>> library): >>> (using a short example to keep it >>> readable) >>> (indexed "Now is") >>> -> ([0 \N] [1 \o] [2 \w] [3 \space] [4 \i] [5 \s]) >>> >>> What I would like to do is only index those elements that satisfy some >>> predicate, such as: >>> (indexed-pred vowel? "Now is") >>> -> ([\N] [0 \o] [\w] [\space] [1 \i] [\s]) >>> >>> I want the counter to only increment when the predicate is true, so just >>> filtering out the index on a fully indexed list isn't what I need, it will >>> leave holes in the numbering. >>> >>> >>> I'd be OK with the return result being: ([nil \N] [0 \o] [nil \w] [nil >>> \space] [1 \i] [nil \s]) >>> since a simple map could strip the nils out. >>> >>> I can't help feeling that the solution is just on the edge of my >>> peripheral vision, but I can't see it. >>> >>> Thanks, >>> -Doug >>> >>> >>> P.S. I want to use this to number the instructions in a road rally, where >>> the sequence of instructions are interspersed with other notes and items. >>> Numbering the vowels in a string is a nice simplification. >>> >>> -- >>> 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 >>> >>> To unsubscribe from this group, send email to >>> clojure+unsubscribegooglegroups.com or reply to this email with the words >>> "REMOVE ME" as the subject. >>> >> >> -- >> 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 >> >> To unsubscribe from this group, send email to >> clojure+unsubscribegooglegroups.com or reply to this email with the words >> "REMOVE ME" as the subject. >> > > -- > 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 > > To unsubscribe from this group, send email to > clojure+unsubscribegooglegroups.com or reply to this email with the words > "REMOVE ME" as the subject. > -- 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 To unsubscribe from this group, send email to clojure+unsubscribegooglegroups.com or reply to this email with the words "REMOVE ME" as the subject.
