On Saturday 29 November 2008 06:27, Ralf Bensmann wrote: > Thanks for clarification. But I am wondering about a function can > return nil: > > user=> (fn [] ((+ 1 2) nil)) > #<user$eval__63$fn__65 [EMAIL PROTECTED]> > > But "just returning nil" is not ok? > user=> (fn [] (nil))
You're not returning nil, you're trying to apply nil (as if it were a function) to an empty argument list. > java.lang.NullPointerException (NO_SOURCE_FILE:24) > user=> (fn [] ((nil))) > java.lang.NullPointerException (NO_SOURCE_FILE:25) Now you're trying to apply the result of applying nil to an empty argument list to an empty argument list. Naturally, it fails at the same point, which is the inner attempt. It's just simpler than you're trying to make it: user=> ((fn [] nil)) nil > Thanks > -Ralf Randall Schulz --~--~---------~--~----~------------~-------~--~----~ 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 To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/clojure?hl=en -~----------~----~----~----~------~----~------~--~---
