99 Clojure Problems – 21: Insert an Element at a given Position into a List

Example:

(deftest p21-insert-at
  (is (= '(1 new 2 3 4) (insert-at 'new 1 '(1 2 3 4)))))

Solution:

My solution to this problem is based on the same idea as the previous one: Reuse split from problem 17 to cut the input sequence into two parts. Then concatenate the parts, cons'ing the element to insert to the tail before doing so.

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