Closure Compiler不会缩小匿名函数中的函数

Question

I have this piece of code, compiled from TypeScript to JavaScript, that I want to minify with the Google Closure Compiler:

var api;
(function (api) {
    function connect() {
        console.log("connected!");
    }
    api.connect = connect;
})(api || (api = {}));
api.connect();

This is compiled to:

var a;
(function(b) {
  b.connect = function() {
    console.log("connected!");
  };
})(a || (a = {}));
a.connect();

As you can see, the name of the connect function inside the anonymous function is not renamed to something like a or b .

How can I tell the compiler to minify the name of the connect function?

EDIT:

Seems like this is because connect is a reserved word. When I replace connect with connectt , the problem is gone.

var api;
(function (api) {
    function connectt() {
        console.log("connected!");
    }
    api.connectt = connectt;
})(api || (api = {}));
api.connectt();

Compiles to:

var a;
(function(b) {
  b.a = function() {
    console.log("connected!");
  };
})(a || (a = {}));
a.a();

Thanks to @A. Andres !

Answer 1

Some properties won't be renamed because they are declared in an externs file . If the compiler can't decide whether a property is part of an external dependency then it won't be renamed.

In your specific case, I can see that there is a method called connect that is part of the Web Audio API in externs/browser/w3c_audio.js ( AudioNode.prototype.connect ).

Property renaming is explained in great detail in the Closure Compiler FAQ and the blog posts mentioned there.

Answer 2

The problem is how you are passing your namespace in via an IIFE argument. If you avoid that, you get the results you want.

const api = {};
(function () {
  function connect() {
    console.log("connected!");
  }
  api.connect = connect;
})();
api.connect();

The compiler doesn't recognize api as a type and therefore doesn't have enough information to differentiate the properties from other objects. By avoiding the alias created by the IIFE call and using const to tell the compiler that api is a namespace, you can get the optimizations you seek.