Inheritance: QueryToken
 public StepMultiplierToken(StepToken parent, decimal multiplier)
 {
     this.parent     = parent ?? throw new ArgumentNullException(nameof(parent));
     this.Multiplier = multiplier;
 }
 public StepMultiplierToken(StepToken parent, decimal multiplier) : base(parent)
 {
     this.Multiplier = multiplier;
 }
 public StepMultiplierToken(StepToken parent, decimal multiplier) : base(parent)
 {
     this.Multiplier = multiplier;
 }