this doesn't work:
user= (defn if-a [a b] (if (a) (str a) (str b)))
#'user/if-a
user= (if-a nil b)
java.lang.NullPointerException (NO_SOURCE_FILE:0)
user= (if-a a nil)
user= java.lang.ClassCastException: java.lang.String cannot be cast
to clojure.lang.IFn (NO_SOURCE_FILE:0)
this does work:
You have an extra set of parens around a, treating it as a function call. Try:
(defn if-a [a b] (if a (str a) (str b)))
Hope that helps,
Dave
On Tue, Aug 23, 2011 at 4:37 PM, Andrew Xue and...@lumoslabs.com wrote:
this doesn't work:
user= (defn if-a [a b] (if (a) (str a) (str b)))
user= (defn if-a [a b] (if (a) (str a) (str b)))
The problem is (a) - it tries to call a as a function, which
throws NullPointer if a is nil. You meant:
user= (defn if-a [a b] (if a (str a) (str b)))
mg
On Tue, Aug 23, 2011 at 9:37 PM, Andrew Xue and...@lumoslabs.com wrote:
this
