Explicitly mentioned here: https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/proposa
Explicitly mentioned here: https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-10.0/record-structs#allow-with-expression-on-structs
This feature specification describes record structs, which are structs where the compiler generates methods similar to those for record classes.
