On Jun 27, 11:32 am, Meikel Brandmeyer <m...@kotka.de> wrote: > Am 26.06.2009 um 23:44 schrieb Michael Spiegel: > > =>(def foo (sorted-set "bob" "alice" "michael")) > > => (contains? foo 5) > > java.lang.ClassCastException: java.lang.String cannot be cast to > > java.lang.Number (NO_SOURCE_FILE:0) > > IIRC, this came up already. And the general result was, > that it is a bug in the user code to compare an Integer > with a String. > > A sorted-set is not a usual set. It contains elements, > which can be sorted according to an ordering. > Comparing two things, where one is not in the domain > of the ordering, is not defined.
I'd agree that a ClassCastException is not inappropriate if you try to put heterogeneous objects into a sorted-set. But contains? should probably just return true or false, never throw. Michael's set doesn't contain 5; asking whether it does does not seem to me to be an error. I think it would be desirable for contains? to have returned false. A simple, crude way to make it do so would be to wrap the original contains? code in a try ... catch that catches ClassCastException and returns false if one gets thrown. --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
