Boolean passed to string parser to specify how escapes should be handled. See parseString for details.
iopipe from which to parse item. If needed, it may be extended.
Current position in the iopipe's window from which the next item should start. Leading whitespace is allowed.
If the stream contains a valid JSON item, the details about that item are returned. If the stream does not contain any more items, then EOF is returned. If there is an error parsing data from the stream for any reason, then Error is returned.
Obtain one parsing item from the given iopipe. This has no notion of context, so it does not actually validate the overall structure of the JSON stream. It only confirms that the next item is a valid JSON item.