In Clojure, empty sequences are not considered logically false, so
your code continues going after reducing col to an empty list. You
need to explicitly check whether the collection is empty, like so:
(defn list-length [col]
(if (empty? col)
0
(+ 1 (list-length (rest col)))))
Cheers,
Nadeem
On Sun, Dec 5, 2010 at 11:52 PM, HB <hubaghd...@gmail.com> wrote:
> Hi,
> I'm trying to write a function that calculates the length of a list:
>
>
> (defn list-length [col]
> (if col
> (+ 1 (list-length(rest col)))
> 0))
>
>
> (list-length '(Java, Clojure, Scala))
>
> Upon running it in the REPL, I got the error:
> java.lang.StackOverflowError (test.clj:3)
>
> What is going wrong?
>
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