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You're viewing version 1.2.0 of fn?. The latest stable version of Clojure Core is 1.3.0.

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1.2.0

1.2.0
1.3.0

fn?

clojure.core

(fn? x)

Returns true if x implements Fn, i.e. is an object created via fn.

© Rich Hickey. All rights reserved. Eclipse Public License 1.0

2 Examples top

link | changes
```
user=> (fn? 5)
false
user=> (fn? inc)
true
user=> (fn? (fn []))
true
user=> (fn? #(5))
true
```
user=> (fn? 5) false user=> (fn? inc) true user=> (fn? (fn [])) true user=> (fn? #(5)) true
link | changes
```
;; Even though maps, sets, vectors and keywords behave as functions:
user=> ({:a 1} :a)
1

;; fn? still returns false for them because they are not created using fn:
user=> (fn? {:a 1})
false
```
;; Even though maps, sets, vectors and keywords behave as functions: user=> ({:a 1} :a) 1 ;; fn? still returns false for them because they are not created using fn: user=> (fn? {:a 1}) false

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See Also top

0
clojure.core/ifn?
Returns true if x implements IFn. Note that many data structures (e

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Source clojure/core.clj:4989 top

(defn fn?
  "Returns true if x implements Fn, i.e. is an object created via fn."
  {:added "1.0"}
  [x] (instance? clojure.lang.Fn x))

© Rich Hickey. All rights reserved. Eclipse Public License 1.0

Vars in clojure.core/fn?: defn instance?

Used in 7 other vars trampoline function? function? query-dataset query-to-pred eval-in-project run-test

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