Function insert

insert<T>(array, index, value): void
Insert a value into an array at a specific index.
Type Parameters
- T
Parameters
- array: T[]
  The array of interest.
- index: number
  The index at which to insert the value. Negative values are taken as an offset from the end of the array.
- value: T
  The value to set at the specified index.
  
  Complexity
  Linear.
  
  Undefined Behavior
  An index which is non-integral.
  
  Example
```
import { ArrayExt } from '@lumino/algorithm';

let data = [0, 1, 2];
ArrayExt.insert(data, 0, -1);  // [-1, 0, 1, 2]
ArrayExt.insert(data, 2, 12);  // [-1, 0, 12, 1, 2]
ArrayExt.insert(data, -1, 7);  // [-1, 0, 12, 1, 7, 2]
ArrayExt.insert(data, 6, 19);  // [-1, 0, 12, 1, 7, 2, 19]
```
Returns void
- Defined in array.ts:1081