Add And Remove Specific Array Elements Using Array.splice()

Is it possible to add to a specific part of an array, and then deleting a specific part of the array, in this case the end value using arr.splice()? i currently do this like so: v

Solution 1:

In answer to my original question as confirmed in the comments. It is not possible to provide a separate index to insert and another to remove in an array using the splice method or potentially any other single statement in javascript. The best approach to try to achieve this in a single statement if i really needed it would be to create your own function, which really seems counter productive for the most part.

Solution 2:

You can use Array.from() to set the .length and values of specific indexes of an array in a single call

var arr = [1,2,3,4,5,6,7,8,9];

arr = Array.from({length:arr.length - 1, ...arr, 0:"test"});

console.log(arr);

To achieve the pattern described at Question you can alternatively use a loop and Object.assign()

var arr = [1,2,3,4,5,6,7,8,9];
var n = 0;
var prop = "test";
while (arr.length > 1) {
  Object.assign(arr, {length:arr.length -1,...arr, [n]:!n ? prop : prop+n});
  ++n;
  console.log(arr);
}