Support for serializing to Spans about memorypack HOT 1 CLOSED

[ThreadStatic]
static ArrayBufferWriter<byte>? threadStaticBufferWriter;

public void Do<T>(in T? value)
{
    var bufferWriter = threadStaticBufferWriter;
    if (bufferWriter == null)
    {
        bufferWriter = threadStaticBufferWriter = new ArrayBufferWriter<byte>();
    }
    else
    {
        bufferWriter.Clear();
    }

    MemoryPackSerializer.Serialize(bufferWriter, value);

    var span = bufferWriter.WrittenSpan;
    // do anything...
}