public Expression Visit(LogicTrue constant) { return(constant); }
public T Visit(LogicTrue constant) { return(default(T)); }
public SortedSet <string> Visit(LogicTrue constant) { return(new SortedSet <string> { }); }
public async Task <Value> Visit(LogicTrue constant) { return(await Task.Run(() => new BoolValue(true))); // get rid of compiler warning }