clojure.core/satisfies?

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Type: function Added: Clojure 1.2 Examples: 2 Runnable: 0

([protocol x])

Returns true if x satisfies the protocol

Examples

by Jeff Rose on 2011-01-13 . May have evaluation errors. ▶

(ns foo) (defprotocol Foo (foo [this])) (defprotocol Bar (bar [this])) (extend java.lang.Number Bar {:bar (fn [this] 42)}) (extend java.lang.String Foo {:foo (fn [this] "foo")} Bar {:bar (fn [this] "forty two")}) (satisfies? Foo "zam") ; => true (satisfies? Bar "zam") ; => true (satisfies? Foo 123) ; => false (satisfies? Bar 123) ; => true

by thenonameguy on 2019-05-15 . May have evaluation errors. ▶

;; Note that protocol argument should be the var generated by the ;; defprotocol call, not the Java interface. (ns a) (defprotocol Foo (foo [this])) (ns b (:require [a]) (:import a.Foo)) ;; bad (satisfies? Foo :test) ; => NPE ;; good (satisfies? a/Foo :test) ; => false

Note by huahaiy

Unless this issue is resolved, do not use this function in a hot path, for it is extremely slow. See also this post

See also

• clojure.core/extend (0)
• clojure.core/defprotocol (2)
• clojure.core/instance? (0)
• clojure.core/extends?
• clojure.core/extenders

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