public static bool IsKnown(this ILearnDirectClassSystemCode source) => source != null && !string.IsNullOrWhiteSpace(source.Code) && !source.Code.CaseInsensitiveEquals("NUL");
/// <summary> /// Determines whether this instance is known. /// </summary> /// <param name="source">The source.</param> /// <returns> /// <c>true</c> if this instance is known; otherwise, <c>false</c>. /// </returns> public static bool IsKnown(this ILearnDirectClassSystemCode source) => It.Has(source) && It.Has(source.Code) && !source.Code.ComparesWith("NUL");