### 6.3.9 Inserting an element into a list or a string

The insert command inserts elements into a list or string.

- insert takes three arguments:
  - L, a list or a string.
  - i, an integer (the index).
  - x, an object.
- insert(L,i,x) returns L with x inserted at index i and the necessary elements shifted to the right.

#### Examples

insert([3,4,2],2,5)

| ⎡ ⎣ | 3,4,5,2 | ⎤ ⎦

insert("342",2,"5")

“3452” |  |  |  |  |  |  |  |  |  |

insert returns an error if the index is too large.

insert([3,4,2],4,5)

| insert([3,4,2],4,5) |  |  |  |  |  |  |  |  |
| Error: Invalid dimension |  |  |  |  |  |  |  |  |