Oke, So you convert the coll first to a sequence and compared it to the reverse. Does the reversed coll not to be converted to a sequence then?
Op donderdag 8 oktober 2015 14:10:43 UTC+2 schreef Marc O'Morain: > This should do it: > > (defn palindrome? [coll] > (= (seq coll) (reverse coll))) > > > user=> (palindrome? "tattarrattat") > true > user=> (palindrome? [1 5 10 10 5 1]) > true > user=> (palindrome? "marc") > false > user=> (palindrome? [1 2 3]) > false > > > On 8 October 2015 at 12:48, r/ Wobben <wobb...@gmail.com <javascript:>> > wrote: > >> Chjips you are right. See this : >> >> (defn palindrome [x] >> (if (string? x) >> (clojure.string/reverse x) >> (into (empty x) (reverse x)))) >> >> (palindrome '( 1 2 3 4)) (1 2 3 4) >> >> So back to the drawing table. >> >> Roelof >> >> >> Op donderdag 8 oktober 2015 10:59:30 UTC+2 schreef Alan Forrester: >> >>> On 8 Oct 2015, at 09:15, r/ Wobben <wobb...@gmail.com> wrote: >>> >>> > I have now this : >>> > >>> > (ns fourclojure.core >>> > (:gen-class)) >>> > >>> > >>> > (defn checker [x] >>> > ( = x (if (string? x) >>> > (clojure.string/reverse x) >>> > (into (empty x) (reverse x))))) >>> > >>> > >>> > (checker '(1 2 3 4 5)) true >>> > >>> > >>> > ( = '( 1 2 3 4 5) '( 5 4 3 2 1) ) false >>> > >>> > So something is wrong about my code >>> > >>> > it works fine with string but not with a set >>> >>> First, ‘(1 2 3 4 5) is a list, not a set. >>> >>> Second, (reverse ‘(1 2 3 4 5)) is ‘(5 4 3 2 1) and according to the >>> docs for into >>> >>> https://clojuredocs.org/clojure.core/into >>> >>> that function conjoins items from (reverse ‘(1 2 3 4 5)) onto (empty >>> ‘(1 2 3 4 5)). The docs for conj tell you what will happen >>> >>> https://clojuredocs.org/clojure.core/conj >>> >>> (empty ‘(1 2 3 4 5)) is a list and conjoining to a list puts items at >>> the front of the list not the back, so it puts 5 in at the from, then puts >>> 4 in front of the 5 and so on. So you are doing ( = '( 1 2 3 4 5) ‘(1 2 3 >>> 4 5)). >>> >>> Alan >> >> -- >> 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/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.
