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JavaScript React by Example Building the Application Removing Names From the List

Just wondering why Guil uses index + 1?

As I know that index indicates to the current item in the array but, what he does mean by + 1?

1 Answer

Clayton Perszyk
Clayton Perszyk
Treehouse Moderator 46,861 Points
let guests = ["tom", "dick", "jane", "louis", "dave"];
let guestsAfterSlicing = [];
let index = 2;
let firstHalf = guests.slice(0, index); // returns tom and dick, so everything from index 0 to index 2 (non-inclusive)
let secondHalf = guests.slice(index + 1); // returns louis and dave, so everything from index 3 to end of array

guestsAfterSlicing = firstHalf.concat(secondHalf);
console.log(guestsAfterSlicing); // returns ["tom", "dick", "louis", "dave"];

By performing the previous operations we have removed jane from the original guests array.

Thanks a lot!