Caches the string so we're not allocating strings just to do facet checks
Retrieve the schema component that gave rise to this infoset item.
Retrieve the schema component that gave rise to this infoset item.
The totalElementCount is the total count of how many elements this InfosetItem contains.
The totalElementCount is the total count of how many elements this InfosetItem contains.
(Used to call this 'size', but size is often a length-like thing, so changed name to be more distinctive)