clojure.core/instance?

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Type: function Added: Clojure 1.0 Examples: 4 Runnable: 0

([c x])

Evaluates x and tests if it is an instance of the class c. Returns true or false

Examples

by gstamp on 2010-08-20 . May have evaluation errors. ▶

(instance? Long 1) true (instance? Integer 1) false (instance? Number 1) true (instance? String 1) false (instance? String "1") true

by shockbob on 2011-08-22 . May have evaluation errors. ▶

(def al (new java.util.ArrayList)) #'user/al (instance? java.util.Collection al) true (instance? java.util.RandomAccess al) true (instance? java.lang.String al) false

by Phalphalak on 2013-01-23 . May have evaluation errors. ▶

;; Some things are more than what they seem to be at first glance (instance? clojure.lang.IFn +) true (instance? clojure.lang.Keyword :a) true (instance? clojure.lang.IFn :a) true (instance? clojure.lang.IFn {:a 1}) true

by mars0i on 2016-12-28 . May have evaluation errors. ▶

;; If `c` is specified with a literal class name, this is a Java ;; class name. If any of the namespace components of the class ;; include dashes, the dashes have to be replaced with underscores: (ns foo-bar) (defrecord Box [x]) (def box (Box. 42)) (instance? foo-bar.Box box) ;=> CompilerException java.lang.ClassNotFoundException: foo-bar.Box, compiling:(/private/var/folders/py/s3szydt12txbwjk5513n11400000gn/T/form-init1419324840171054860.clj:1:1) (instance? foo_bar.Box box) ;=> true ;; This rule doesn't apply to the last component of the class name: (defrecord My-Box [x]) ; not an idiomatic choice (def mybox (My-Box. 42)) (instance? foo_bar.My-Box mybox) ;=> true

See also

• clojure.core/type (0)
• clojure.core/supers (0)
• clojure.core/doto (0)
• clojure.core/class (1)
• clojure.core/satisfies? (0)
• clojure.core/isa? (2)

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Content from the matching ClojureDocs page, with authors credited on each contribution.