@Override
public Boolean visitFunctionHolderExpression(FunctionHolderExpression holder, ErrorCollector errors) {
if(holder.isAggregating()){
for (int i = 0; i < holder.args.size(); i++) {
LogicalExpression e = holder.args.get(i);
if(e.accept(this, errors)){
errors.addGeneralError(e.getPosition(),
String.format("Aggregating function call %s includes nested aggregations at arguments number %d. " +
"This isn't allowed.", holder.getName(), i));
}
}