There's a rule that if something is easy to invent, a bunch of people will whip up their own versions independently, sometimes even within the same organisation.
So for there's...
C# scripting (CSI.exe): https://learn.microsoft.com/en-us/archive/msdn-magazine/2016...
PowerShell Add-Type that allows one-file inline C# scripting: https://learn.microsoft.com/en-us/powershell/module/microsof...
The Roslyn .CSX script files (RCSI.exe): https://devblogs.microsoft.com/visualstudio/introducing-the-...
.NET Interactive: https://github.com/dotnet/interactive
... and now this.
.net interactive is a kernel based approach for notebooks. CSI is more like a traditional repl (extracted from a VS feature). This here is more like traditional scripting. It is coding without project file. There is no attempt of interactivity here.
What would be really useful is to include one of these with Windows, so that it simply works and can be used for scripting without needing to write a batch file to bootstrap a PowerShell script to bootstrap the .NET runtime to bootstrap the C# scripting environment.
This would basically be VbScript 2.0, and MS killed VbScript because it had become a massive security hole.
> There's a rule that if something is easy to invent, (...)
You seem to be confused. There is nothing being invented in here. What they are announcing is basically an update to the dotnet command line app to support building and running plain vanilla C# programs.
Maybe this iteration it won't be a bolt-on, who knows. Because of the origin of C# (Microsoft Java replacement) it's all still very MSBuild/IDe-magic-ish instead of being its own thing where you can decide your own dependency resolution, your own compiler and your own linker.
It's similar to cmd.exe and conhost etc. It's all tied to decades old legacy baselines that Microsoft just won't or can't let go of.
Reading all the above, this is nothing like that.
It's just standard c# no new dialect, works like a proper 'shell' script and it's not a repl, what am I missing
Indeed, what I find somehow dishonest is the lack of acknowledgement of previous efforts.
The whole presentation at BUILD was done as if it was a great ideas, they only thought about it now.