Indicates one of the possibilities must be found.
Indicates one of the possibilities must be found. Simplest case for this is a run of optional elements followed by a required element in a sequence. Can also occur if all branches of a choice are Closed. Then the resulting choice possibilities are also Closed.
Indicates that these are possible, but all are optional so a surrounding sequence group on the stack could also provide a matching element.
PNE stands for Possible Next Element.
PNE stands for Possible Next Element.
Allows overriding the isRequiredStreamingUnparserEvent characteristic of a term.
Used when a required ERD appears in a child of a choice. In that case, that ERD is optional since we could be on another choice branch.
Indicates that there should never be any use of possible next elements for the associated Term (QuasiElements is the use case).