clojure.core/list?

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Type: function Added: Clojure 1.0 Examples: 2 Runnable: 2

([x])

Returns true if x implements IPersistentList

Examples

by dpritchett on 2010-07-14 ▶

;; an idiomatic persistent-list is a list (list? '(1 2 3)) ;;=> true ;; a persistent-list is a list ;; (list? (list 1 2)) ;;=> true ;; a numeric value (long) is not a list (list? 0) ;;=> false ;; a persistent-array-map is not a list (list? {}) ;;=> false ;; a persistent-vector is not a list (list? []) ;;=> false ;; a lazy-sequence is not always a list (list? (range 10)) ;;=> false

by muhuk on 2015-11-30 ▶

;; not all lists are lists (cons 1 '(2 3)) ;; => (1 2 3) (= '(1 2 3) (cons 1 '(2 3))) ;; => true (list? (cons 1 '(2 3))) ;; => false ;; good news is: (seq? (cons 1 '(2 3))) ;; => true (seq? [1 2 3]) ;; => false ;; So seq? might be what you are looking ;; for when you want to test listness.

Note by steveminer

You may want to use seq? instead of list?, especially if you might be dealing with a lazy sequence as returned by filter, range, etc.

See also

• clojure.core/seq? (2)
• clojure.core/sequential? (1)
• clojure.core/coll? (4)
• clojure.core/map? (1)
• clojure.core/set?
• clojure.core/vector? (2)

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