I am using Personas which relies on the proprietary property navigator.id. Since this property is not standard, the TypeScript compiler generates the following warning:

$ tsc home.ts --out my_ts_generated_code.js

/Users/..../home.ts(27,18): The property 'id' does not exist on value of type 'Navigator'

But the .js file is successfully generated and runs on the FF15 browser without any warning/error message.

I also include a polyfill for navigator.id, as instructed by the documentation, so navigator.id will definitely by available in every browser.

Could someone suggest me how to deal with this warning?

index.html

<!-- some HTML omit above -->

<script src=https://login.persona.org/include.js></script>

<script src=my_ts_generated_code.js></script>

<button class=btn id=signin>Sign in</button>

<button class=btn id=signout>Sign out</button>

<!-- some HTML omit below -->

home.ts

declare var $;



class Student {

    fullname : string;

    constructor(public firstname, public middleinitial, public lastname) {

        this.fullname = firstname +   + middleinitial +   + lastname;

    }

}



interface Person {

    firstname: string;

    lastname: string;

}



function greeter(person : Person) {

    return Hello,  + person.firstname +   + person.lastname;

}



var user = new Student(Jane, M., User);



$(function() {

    $('#signin').on('click', function(e) {

        e.preventDefault();

        navigator.id.request();

    });



    $('#signout').on('click', function(e) {

        e.preventDefault();

        navigator.id.logout();

    });

    //document.body.innerHTML = greeter(user);

});