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javascripttypescriptrevealing-module-pattern

TypeScript code similar to Revealing Module Pattern structure


I want to convert some JavaScript code I've written into TypeScript. I'm rather new to TypeScript syntax and way of thinking, as a JavaScript developer.

What is giving me a headache is the hard time I've had to convert some piece of code that uses the Revealing Module Pattern into TypeScript.

One example is the below:

//JS Code
var obj;

//code...
(function(){
    function myFunction(){
        //do work
    }


    function MyOtherConstructor(){
        return {
            publicMethod: myFunction
        }
    }

    obj = new MyOtherConstructor();
})();

//use obj.publicMethod in code later

One workaround I've thought was this:

//TypeScript code
var obj;

class MyOtherConstructor {
        private callback: any;
        constructor(f: any){
            this.callback = f;
        }
        publicMethod(): any{
            this.callback();
        }
}
//code...
(() => {
    function myFunction(){
        //do work
        console.log("Called myFunction");
    }
    obj = new MyOtherConstructor(myFunction);
})();

//use obj.publicMethod in code later

which works, but it's ugly.

Any suggestion how make this better?


Solution

  • If you need a single object obj, then do not use a class. A namespace is more adapted:

    namespace obj {
        function myFunction() {
            // ...
        }
        export var publicMethod = myFunction;
    }
    

    If you prefer to keep the class, then here is a more concise code for it:

    class MyOtherConstructor {
        constructor(public publicMethod: () => void) {
        }
    }