NullMatch.yes means a rule can succeed while consuming no input. For example e? or e*, for all expressions e.
Nullmatch.no means a rule will always consume at least a token while succeeding.
Nullmatch.indeterminate means the algorithm could not converge.
NullMatch.yes means a rule can succeed while consuming no input. For example e? or e*, for all expressions e. Nullmatch.no means a rule will always consume at least a token while succeeding. Nullmatch.indeterminate means the algorithm could not converge.