Function once

once<T>(value): IterableIterator<T>
Create an iterator which yields a value a single time.
Type Parameters
- T
Parameters
- value: T
  The value to wrap in an iterator.
Returns IterableIterator<T>
A new iterator which yields the value a single time.

Example
```
import { once } from '@lumino/algorithm';

let stream = once(7);

Array.from(stream);  // [7]
```
Deprecated
- Defined in repeat.ts:55