user=> (let [a (array-map Double/NaN 1)] (assoc a (key (first a)) "foo"))
{NaN 1, NaN "foo"}
user=> (let [a (hash-map Double/NaN 1)] (assoc a (key (first a)) "foo"))
{NaN "foo"}
Approach: Array-map's comparison skips identity-check and always delegates to .equals calls. The attached patch alignes array-map behaviour with hash-map by doing the appropriate pointer checks before delegating to .equals
