functions as parameters

This is a fragment from the book “Beginning Javacript 5th edition”.
Chapter X :

This also means we can pass a function to another function’s parameter. Take a look at the following code:

[CODE]
function doSomething(fn) {
fn(“Hello, World”);
} doSomething(alert);[/CODE]

This code de nes a function called doSomething(), and it has a single parameter called fn. Inside the function, the fn variable is used as a function; it’s executed by using the fn identi er followed by a pair of parentheses.

What situations would be usefull for using a function as another function parameter? aside from this alert() example ?

Thanks in advance!
Bruno.

Also in #JavaScript _↴