Incorrect type inferred for 'this' in instance methods

[Cakez0r]

Given a class

class Foo {
    private baz: string;

    public bar() {
        var x = this;

        console.log(x.baz);
    }
}

The compiler infers 'this' to be of type 'Foo' within the 'bar' function. However, the type of 'this' is not guaranteed to be 'Foo'.

Consider

var y = new Foo();
setTimeout(y.bar, 1000);

Given this possibility, should the type of 'this' within 'bar' be 'any' instead of 'Foo'?

[danquirk]

In practice the majority of the time people use this in a class they'll want it to be typed as Foo. There're ways around this as you noted but it would be unfortunate to degrade the core class scenarios for that. There are a variety of improvements we are hoping to make to this typing one day though, see #513