When you want to pull multi-gig JSON files and not wait for the full file before processing is where I first used this.

Funnily enough, this was one of the first users of jsonriver at google. A team needed to parse more JSON than most JS VMs will allow you to fit into a single string, so they had no choice but to use a streaming parser.

When its closing brace or square bracket appears.

EDIT: this is totally wrong and the question is right.

Actually, not quite how this works. You always get valid JSON, as in this sequence from the readme:

```json {"name": "Al"} {"name": "Ale"} ```

So the braces are always closed