Question

http://jsfiddle.net/raylu/C6Tkn/

function a() {
    document.write(this + '<br />');
}

a();
a.apply('hello');

var b = function() {
    a();
}
b.apply('hi');​

I would expect the last line to output ‘hi’, but instead it outputs window.

Answer 1

The this is meant to be window in that context.

b()‘s this is 'hi', but that isn’t inherited/associated with any function calls in the body of the b() function. That is why this inside of a() when called via b() with the normal function invocation method (()) is window.