Modern library authoring

[vanillajonathan]

If you're writing a library you're probably targeting netstandard2.0 which can be quite frustrating since you cannot use modern features such as implicit usings, file-scoped namespaces or nullable references types.

Please improve the library authoring developer experience by supporting modern features and development practices such as implicit usings, file-scoped namespaces and nullable references types.

[teo-tsirpanis]

Hello! C# versions larger than 7.3 are not officially supported in .NET Standard 2.0. However you can opt in to the latest language version by adding the <LangVersion>latest</LangVersion> property in your project file.

[vanillajonathan]

Yes, I am aware of that. I would like to see official support for newer versions of C# in .NET Standard 2.0 and a better out-of-the-box experience when scaffolding a new library project.

[teo-tsirpanis]

I don't think this is going to happen. New language versions depend on attributes that don't get backported to earlier frameworks.

[vanillajonathan]

Yeah, I can understand not everything can be backported (such as records, init-setters, etc), but file-scoped namespaces and implicit using sounds like something that maybe could be backported. Either way, I think Microsoft someway, somehow should improve the library authoring process because it feels outdated.

[huoyaoyuan]

You can use libraries like PolySharp to fulfill some attributes for down level frameworks.
For me, I'm dropping .NET Framework and .NET Standard in my libraries when more feature and scenarios are supported by .NET Core.

[vanillajonathan]

Then what do you target and how do you distribute such a library? You going to target net6.0 or multi-target net5.0;net6.0;net7.0;net8.0?

[huoyaoyuan]

A reasonable lowest like net5.0 or net6.0, plus the current version.

[vanillajonathan]

But does that work across all the .NET versions between the lowest and the current? Or do I have to add a target moniker for every version between the lowest and the current version?

[huoyaoyuan]

Or do I have to add a target moniker for every version between the lowest and the current version?

Every version between them will resolve to the lower version as a fallback.