protocol implementation in cljs

00-input.cljs

;; dummy protocol
(defprotocol IFoo
  (foo [this]))

;; dummy cljs type
(deftype Bar [])

;; extending a cljs type
(extend-type Bar
  IFoo (foo [this] (println "Hello from IFoo.foo for Bar")))

;; extending a js type
(extend-type js/Function
  IFoo (foo [this] (println "Hello from IFoo.foo for js/Function")))

;; extending a js base type
(extend-type number
  IFoo (foo [this] (println "Hello from IFoo.foo for number")))

01-output.js

//// cljs.user=> (extend-type Bar IFoo (foo [this] (println "Hello from IFoo.foo for Bar")))
(function() {
    cljs.user.Bar.prototype.cljs$user$IFoo$ = true;

    return cljs.user.Bar.prototype.cljs$user$IFoo$foo$arity$1 = (function(this$) {
        var this$__$1 = this;
        return cljs.core.println.call(null, "Hello from IFoo.foo for Bar");
    });
})()

//// cljs.user=> (extend-type js/Function IFoo (foo [this] (println "Hello from IFoo.foo for js/Function")))
(function() {
    Function.prototype.cljs$user$IFoo$ = true;

    return Function.prototype.cljs$user$IFoo$foo$arity$1 = (function(this$) {
        var this$__$1 = this;
        return cljs.core.println.call(null, "Hello from IFoo.foo of js/Function");
    });
})()

//// cljs.user=> (extend-type number IFoo (foo [this] (println "Hello from IFoo.foo for number")))
(function() {
    (cljs.user.IFoo["number"] = true);

    return (cljs.user.foo["number"] = (function(this$) {
        return cljs.core.println.call(null, "Hello from Foo.foo of number");
    }));
})()

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