using System;

using System.Runtime.InteropServices;

using System.Runtime.CompilerServices;

​

a? res = new a(123);

Console.WriteLine(new { res?.b });

{

    ref readonly T AsRef<T>() where T : struct => ref MemoryMarshal.AsRef<T>(res.Value.bin);

    ref readonly var aa = ref AsRef<a>();

    Console.WriteLine(new { aa.b });

}

​

{

    ref readonly T AsRef<T>() where T : struct => ref MemoryMarshal.AsRef<T>(res.Value.bin);

    ref readonly var aa = ref AsRef<a>();

    Console.WriteLine(new { aa });

}

​

{

    ref readonly T AsRef<T>() where T : struct => ref MemoryMarshal.AsRef<T>(res.Value.bin);

    var aa = AsRef<a>();

    Console.WriteLine(new { aa.b });

}

​

{

    ref readonly a AsRef() => ref MemoryMarshal.AsRef<a>(res.Value.bin);

    var aa = AsRef();

    Console.WriteLine(new { aa.b });

}

​

{

    ref readonly var aa = ref MemoryMarshal.AsRef<a>(res.Value.bin);

    Console.WriteLine(new { aa.b });

}

​

record struct a(UInt16 b) {

    public ReadOnlySpan<byte> bin => MemoryMarshal.AsBytes(new ReadOnlySpan<a>(in Unsafe.AsRef(in this)));

}