When should I use call() vs invoking the function directly?

Question

I\'ve got a JavaScript application that uses a lot of callbacks. A typical function will take a callback, and wrap it with another callback.

Namespace.foo = func         


        

Answer 1

call() is used to change the this value of the function:

var obj = {a: 0};
method.call(obj, "parameter");
function method(para) {
    this.a == 0; // true <-- obj is now this
}