aliasForProductionChild method
Implementation
int? aliasForProductionChild(int productionId, int childIndex) {
if (productionId < 0 ||
productionId >= aliasSequences.length ||
childIndex < 0 ||
childIndex >= aliasSequences[productionId].length) {
return null;
}
final symbol = aliasSequences[productionId][childIndex];
return symbol == 0 ? null : symbol;
}