Insert and remove elements at positions in an Array in Javascript

arrinsrem.js

Array.prototype.remove = function(index) {
  delete this[index];
  for (var i = index + 1; i < this.length; i++)
    this[i-1] = this[i];
  this.pop();
}
Array.prototype.insert = function(index, value) {
  this.unshift(undefined);
  for (var i = 0; i < index + 1; i++)
    this[i-1] = this[i];
  this[index] = value;
}

Use as follows:

yourarray = ['a', 'b', '1', 'c', 'd', 'e', 'f']
yourarray.remove(2);

yourarray = ['a', 'b', 'd', 'e', 'f']
yourarray.insert(2, 'c');