Using arrow function as callback function can reduce lines of code.
The default syntax for arrow function is
() => {}
This can be used as callbacks
For example if we want to print all elements in an array [1,2,3,4,5]
without arrow function, the code will look like this
[1,2,3,4,5].forEach(function(x){
console.log(x);
}
With arrow function, it can be reduced to
[1,2,3,4,5].forEach(x => console.log(x));
Here the callback function function(x){console.log(x)}
is reduced to x=>console.log(x)