"
Negative indexing (.at(-1)): When indexing an array or a string, at can be used to
index from the end. It’s equivalent to arr[arr.length - 1)
"
sic arr[arr.length-1)
This is wrong. Array.at can get, but not set the value. So they're not equivalent.
console.log( arr[arr.length-1] ); // works
arr[arr.length-1] = 1; // works
console.log( arr.at(-1) ); // works
arr.at(-1) = 1; // ReferenceError: Invalid left-hand side in assignment
This is wrong. Array.at can get, but not set the value. So they're not equivalent.
console.log( arr[arr.length-1] ); // works
arr[arr.length-1] = 1; // works
console.log( arr.at(-1) ); // works
arr.at(-1) = 1; // ReferenceError: Invalid left-hand side in assignment