What is the necessity of having (item, index, and array) in iterative methods within JavaScript?

Currently engrossed in dive into the world of javascript with "professional javascript for web developers", focusing on the discussion about iterative methods for arrays such as every(), filter(), and more.

The book mentions that you need to pass functions that take three arguments: the value of the array item, the position of the item in the array, and the array object. This means all functions should look something like this:

function(item, index, array){

[do something with item]

}

But why exactly would you need to include the index and array arguments? Wouldn't just using item suffice?

javascript

Answer №1

In JavaScript, the number of arguments passed to a function is not taken into account. Therefore, if you do not require the index or arguments for any particular reason, you can simply pass a function that accepts the item.

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