map destructuring: prevent evaluation of values in :or when they are not used/needed

Question

The name :or implies this should behave as "or" and be "lazy" but it's not the case currently.
The following gist shows the issue. :x is present in the map but we eval the default value:


(defn foo
  [{:keys [x]
    :or {x (println :set-default)}}]
  x)
 
 
 
user> (foo {:x 1})
:set-default
1

Answer 1

Comment made by: gshayban

1.2 - current all behave this way, doesn't seem like a recent change.

Answer 2

Comment made by: mpenet

Right, I thought it might have been a regression, but wasn't sure at all.
It seems it would be safe to change the current behavior, I doubt it would break any ones code.

Answer 3

Reference: https://clojure.atlassian.net/browse/CLJ-1676 (reported by mpenet)