Hi, I've been developing with JS for a while, and while I know that code below works, I don't really understand why it works.
The way I see it, I've defined testString in testClosure function, and I'm expecting that variable to 'go away' when testClosure function is done, since it's local variable.
However, when I call inner function with a timer, it's still aware of testString variable. Why? Isn't that variable gone five seconds ago when testClosure finished executing? Does the inner function get reference to all variables within testClosure, and they stay valid until all inner functions are done?
function testClosure() {
var testString = 'hai';
// after 5 seconds, call function below
window.setTimeout(function() {
// check if function knows about testString
alert(testString);
}, 5000);
}
testClosure();