getSingleViableAlt static method
Implementation
static int getSingleViableAlt(List<BitSet> altsets) {
final viableAlts = BitSet();
for (var alts in altsets) {
final minAlt = alts.nextset(0);
viableAlts.set(minAlt);
if (viableAlts.cardinality > 1) {
// more than 1 viable alt
return ATN.INVALID_ALT_NUMBER;
}
}
return viableAlts.nextset(0);
}