Question

I wrote such object literal in TypeScript:

var object = {
    message: "Say",
    say: () => {
        return this.message;
     }
};

And I got such generated JavaScript:

var object = {
    message: "Say",
    say: function () {
        return _this.message;
    }
};

Shouldn’t there be such line before return statement:

 var _that = this;

as I am using arrow function expression?

Answer 1

You’re correct. It’s missing the :

var _this = this;

This is discovered after the release(0.8) and is currently fixed on the developer branch.

Note:
Also I think you wanted to write

var object = {
    message: "Say",
    say: function () {
        return () => this.message;
    }
};

which will actualy print Say when it’s run.
See: http://wiki.ecmascript.org/doku.php?id=harmony:arrow_function_syntax