public static T ContextualizeValueType <T>(T?overridingValue, T defaultValue) where T : struct
 {
     return(OverrideConvention.IsOverridden(overridingValue)
         ? overridingValue.Value
         : defaultValue);
 }
 public static T Contextualize <T>(T overridingValue, T defaultValue = default)
 {
     return(OverrideConvention.IsOverridden(overridingValue)
         ? overridingValue
         : defaultValue);
 }