parse/duplicate-items-in-set

This happens when the same item appears more than once in a set literal. For example:

#{:foo :foo}

This also applies to repeated forms such as:

#{(rand) (rand)}

Mitigations

Remove the duplicate item so each set element appears only once. If you need separate computed values, bind them in a let first and build the set from those locals.

(let [a (rand)
      b (rand)]
 #{a b})