(alexandria.0.dev:destructuring-ccase keyform &body clauses) | Function: DESTRUCTURING-CASE, -CCASE, and -ECASE are a combination of CASE and DESTRUCTURING-BIND. KEYFORM must evaluate to a CONS. Clauses are of the form: ((CASE-KEYS . DESTRUCTURING-LAMBDA-LIST) FORM*) The clause whose CASE-KEYS matches CAR of KEY, as if by CASE, CCASE, or ECASE, is selected, and FORMs are then executed with CDR of KEY is destructured and bound by the DESTRUCTURING-LAMBDA-LIST. Example: (defun dcase (x) (destructuring-case x ((:foo a b) (format nil "foo: ~S, ~S" a b)) ((:bar &key a b) (format nil "bar, ~S, ~S" a b)) (((:alt1 :alt2) a) (format nil "alt: ~S" a)) ((t &rest rest) (format nil "unknown: ~S" rest)))) (dcase (list :foo 1 2)) ; => "foo: 1, 2" (dcase (list :bar :a 1 :b 2)) ; => "bar: 1, 2" (dcase (list :alt1 1)) ; => "alt: 1" (dcase (list :alt2 2)) ; => "alt: 2" (dcase (list :quux 1 2 3)) ; => "unknown: 1, 2, 3" (defun decase (x) (destructuring-case x ((:foo a b) (format nil "foo: ~S, ~S" a b)) ((:bar &key a b) (format nil "bar, ~S, ~S" a b)) (((:alt1 :alt2) a) (format nil "alt: ~S" a)))) (decase (list :foo 1 2)) ; => "foo: 1, 2" (decase (list :bar :a 1 :b 2)) ; => "bar: 1, 2" (decase (list :alt1 1)) ; => "alt: 1" (decase (list :alt2 2)) ; => "alt: 2" (decase (list :quux 1 2 3)) ; =| error
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