The call to (index) returns this vector ([0 \:] [1 \a] [2 \space] [3 \4] [4 \space] [5 \:] [6 \b] [7 \space] [8 \1] [9 \space] [10 \:] [11 \c] [12 \space] [13 \3] [14 \space] [15 \:] [16 \d] [17 \space] [18 \4])
And, 3 here is in the 13th position. Your (cond) in index function is picking up the :else branch. On Tue, May 13, 2014 at 6:44 PM, gamma235 <jesus.diama...@gmail.com> wrote: > I am reading The Joy of Clojure now and am finishing chapter 5 on sequence > abstractions. There is an example given that demonstrates how to locate the > index of an element in a sequence by value, but I don't understand why the > character lookup here is returning 13. Can somebody please explain this to > me? > > (defn index [coll] >> (cond >> (map? coll) (seq coll) >> (set? coll) (map vector coll coll) >> :else (map vector (iterate inc 0) coll))) >> >> (defn pos [pred coll] >> (for [[i v] (index coll) :when (pred v)] i)) >> > > >> (pos \3 ":a 4 :b 1 :c 3 :d 4") > > > > => 13 > > > J > > -- > 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. > -- 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.
