I'm trying to work with objects using the property like an index and attempting to make a method that works like the splice method does on arrays [duplicate]

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Closed 2 days ago.

Here is the constructor function along with a push method

function Erray() {
    this.storage = {};
    this.index = 0;
  }
  
  Erray.prototype.push = function(value) {
    this.storage[this.index++] = value;
  }

I also made the 'add' method below...

Erray.prototype.add = function(index, value) {
    for (let i = index ; i <= this.storage.length; i++) {
        if (i = index) {
            break;
        }
        this.storage[i] = this.storage[i-1]
    }
    this.storage[index] = value;
  }

The problem is when I try to call it, I get "array.add is not a function"... Here are the calls I made to test...

let array = new Erray;
  array.push(1)
  array.push(2)
  array.push(3)
  array.add(1,1)

Why is it saying it isn't a function?

function Erray() {
  this.storage = {};
  this.index = 0;
}

Erray.prototype.push = function(value) {
  this.storage[this.index++] = value;
}
Erray.prototype.add = function(index, value) {
  for (let i = index; i <= this.storage.length; i++) {
    if (i = index) {
      break;
    }
    this.storage[i] = this.storage[i - 1]
  }
  this.storage[index] = value;
}
let array = new Erray;
array.push(1)
array.push(2)
array.push(3)
array.add(1, 1)

console.log('done');