Nullable Member Extensions

A handful of base class library members return null as a regular outcome rather than as an error: a type without a base type, an assembly without an entry point, a directory at the root of its drive. Funcky offers each of them as an Option through a C# 14 extension property, so the absence is a None rather than a null check.

Option<Type> baseType = typeof(Foo).BaseTypeOrNone;                 // None for object, interfaces and pointer types
Option<Type> declaringType = typeof(Foo).DeclaringTypeOrNone;       // None for a type that is not nested
Option<MethodInfo> entryPoint = assembly.EntryPointOrNone;          // None for a class library
Option<Exception> cause = exception.InnerExceptionOrNone;           // None without an inner exception
Option<DirectoryInfo> parent = directory.ParentOrNone;              // None for a root directory
Option<Uri> location = response.Headers.LocationOrNone;             // None without a Location header

The properties need the C# 14 compiler. On an older compiler they are available as the static methods the compiler lowers them to, TypeExtensions.get_BaseTypeOrNone(type), which is rarely worth it over Option.FromNullable(type.BaseType). Members that return null from a method call, such as Environment.GetEnvironmentVariable, are out of scope here; wrap them with Option.FromNullable.