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doc source examples comments

1.3.0

empty

clojure.core

(empty coll)

Returns an empty collection of the same category as coll, or nil

2 Examples top

link | changes
```
user=> (empty [1 2 3])
[]
user=> (empty (list 1 2 3))
()
user=> (map empty [[\a \b] {1 2} (range 4)])
([] {} ())
```
user=> (empty [1 2 3]) [] user=> (empty (list 1 2 3)) () user=> (map empty [[\a \b] {1 2} (range 4)]) ([] {} ())
link | changes
```
;; The output will not necessarily be of the same JVM class as the input
user=> (class (seq [1]))
clojure.lang.PersistentVector$ChunkedSeq
user=> (class (empty (seq [1])))
clojure.lang.PersistentList$EmptyList
```
;; The output will not necessarily be of the same JVM class as the input user=> (class (seq [1])) clojure.lang.PersistentVector$ChunkedSeq user=> (class (empty (seq [1]))) clojure.lang.PersistentList$EmptyList

Source clojure/core.clj:4558 top

(defn empty
  "Returns an empty collection of the same category as coll, or nil"
  {:added "1.0"
   :static true}
  [coll]
  (when (instance? clojure.lang.IPersistentCollection coll)
    (.empty ^clojure.lang.IPersistentCollection coll)))

Vars in clojure.core/empty:

Used in 0 other vars

ClojureDocs(beta)

Clojure Core

Namespaces

empty

clojure.core

2 Examples top

See Also top

Source clojure/core.clj:4558 top

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