I ran across this behaviour today: shackles.examples=> (import '[clojure.lang Seqable]) clojure.lang.Seqable shackles.examples=> (deftype Foo [] Seqable (seq [this] ())) shackles.examples.Foo shackles.examples=> (empty? (Foo.)) false shackles.examples=> (deftype Bar [] Seqable (seq [this] nil)) shackles.examples.Bar shackles.examples=> (empty? (Bar.)) true shackles.examples=> (empty? ()) true
Now I understand why this happens - () is truthy but nil is falsey. This seems related to the difference between next and rest. Is there an underlying principle here? -- 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
