The precondition should be a vector of expressions. (defn foo [x] {:pre [(not (nil? x))]} (* 3 x))
On Jan 9, 2012, at 12:53 PM, Tom Chappell wrote: > Ok, I've got a couple thousand lines of Clojure under my belt, but > this has me stumped, unless it's a compiler etc. issue. If I'm > missing something dumb, what is it, please? > > I have a function that is failing a not-nil precondition. Here are > four versions of the same test; only #3 works correctly. Obviously I > can work around the problem, but am I doing something wrong? > > user> (def fq (frequencies "abbccc")) > #'user/fq > > user> fq > {\a 1, \b 2, \c 3} > > user> (fq \a) > 1 > > user> ; incorrectly fails :pre > (defn test-fun1 > [mp k] > {:pre (not (nil? (mp k)))} > (mp k)) > #'user/test-fun1 > > user> (test-fun1 fq \a) > > Assert failed: (nil? (mp k)) > [Thrown class java.lang.AssertionError] -- 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