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# copyWithin()

The `copyWithin()` method copies a sequence of elements within an array and pastes them at a specified position **in-place**, modifying the original array.

## Example

```typescript
const arr: number[] = [ 1, 2, 3, 4, 5 ];
arr.copyWithin( 2, 0, 2 );

console.log( arr ); // Output: [1, 2, 1, 2, 5]
```

* The first argument (`2`) is the target index where the copied elements will be placed.
* The second argument (`0`) is the start index of the elements to be copied.
* The third argument (`2`) is the exclusive end index of the copied elements.

This modifies `arr` to `[1, 2, 1, 2, 5]` by copying elements `1` and `2` and placing them at index `2`, replacing the original values.


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