Currently only vectors and lists implement the stack interfaces, not seqs. I do not think it makes sense for *all* seqs to implement the stack interface. It may not even make sense for any seqs to implement it, but I'd have to think about think about that for a while. Feel free to file an enhancement in jira if you like.
On Saturday, June 11, 2016 at 1:37:26 PM UTC-5, Fluid Dynamics wrote: > > => (pop '(1 2 3)) > (2 3) > => (pop (seq '(1 2 3))) > (2 3) > => ((fn [& xs] (pop xs)) '(1 2 3)) > ClassCastException clojure.lang.ArraySeq cannot be cast to > clojure.lang.IPersistentStack > => (pop (map inc (take 5 (iterate inc 0)))) > ClassCastException clojure.lang.LazySeq cannot be cast to > clojure.lang.IPersistentStack > > That's not right. Pop should act the same as next on all seqs. Instead it > seems to care about details of how the seq was obtained. This clearly > violates least surprise. > > Even wrapping in seq doesn't save you: > > => (pop (seq (map inc (take 5 (iterate inc 0))))) > ClassCastException clojure.lang.Cons cannot be cast to > clojure.lang.IPersistentStack > > This despite (pop (seq '(1 2 3))) working. It *definitely* should be the > case that either (pop (seq x)) works for all non-empty x, or (pop (seq x)) > fails for all non-empty x! > > The obvious fix is to make Cons, LazySeq, ArraySeq, and possibly other > concrete seq/list-type objects that do not already do so implement > IPersistentStack, with peek and pop invoking first and next, respectively. > -- 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.
