> if the key is missing today you'll get nil as the value
You can add a third parameter to override the nil if detecting the missing key matters.
(You almost surely know this, but not all HN commenters will.)
You can add a third parameter to override the nil if detecting the missing key matters.
(You almost surely know this, but not all HN commenters will.)
user> (:bar {:foo 1})
nil
user> (:bar {:foo 1} :missing)
:missing
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