It would be nice if {{assoc-in}} supported multiple key(s)-to-value pairs (and threw an error when there were an even number of arguments, just like {{assoc}}):
user=> (assoc-in {} [:a :b] 1 [:c :d] 2)
{:a {:b 1}, :c {:d 2}}
user=> (assoc-in {} [:a :b] 1 [:c :d])
IllegalArgumentException assoc-in expects even number of arguments after map/vector, found odd number
*Patch:* clj-1771.patch
*Prescreened by:* Alex Miller