Singletons (Autoload) page seems to be wrong for C#

[BigZaphod]

Your Godot version:
v4.0.stable.mono.official [92bee43ad]

Issue description:
I've been assured by my own attempts (and by folks on Discord) that accessing a GDScript Autoload from C# doesn't work quite the way the C# samples on the Autoload page seem to suggest for Godot 4 because the "Global Variable" checkbox in Godot doesn't apparently apply to C#.

I don't know if it worked this way in Godot 3.x or not, though, so it's possible the real issue is incomplete C# support in Godot 4?

For example, this C# sample shown on the page:

var playerVariables = GetNode<PlayerVariables>("/root/PlayerVariables");
playerVariables.Health -= 10; // Instance field.

That code seems to suggest that a type named PlayerVariables should exist in my C# code that was presumably autogenerated by Godot. The screenshot above this example clearly shows "PlayerVariables" is an autoload of a GDScript, but that doesn't seem to make any names exist over on the C# side. As far as I can tell, named classes in GDScript don't show up as types in C# so using GetNode<PlayerVariables>() can't possibly work. It'd be super handy if they did (and maybe they did in 3.X?) but they don't at the moment, anyway, as far as I can tell. Unless I'm doing something wrong.

The next C# sample also seems impossible for those same reasons:

// Static members can be accessed by using the class name.
PlayerVariables.Health -= 10;

I have no idea at this point if this documentation is just totally wrong and made up of wishful thinking, or if it used to work and now doesn't! I do wish it worked, though, and if it's supposed to work, I'd love to know what the heck I'm doing wrong. 😛

URL to the documentation page:
https://docs.godotengine.org/en/latest/tutorials/scripting/singletons_autoload.html

[raulsntos]

The documentation is mainly written with GDScript in mind, excerpts of code are often translated to C# but the rest of the documentation (text and images) can't be changed.

You are looking at the documentation page for Singletons (Autoload), assuming you are using GDScript the image describes how to add a GDScript to the list of autoloads and then the code to retrieve it.

The code to retrieve an autoload is also provided in C#, this code assumes the autoload is also implemented in C#. However, the image still shows GDScript because images can't be changed based on the selected language.

I've been assured by my own attempts (and by folks on Discord) that accessing a GDScript Autoload from C# doesn't work quite the way the C# samples on the Autoload page seem to suggest for Godot 4 [...]

This documentation page is not meant to show how to access GDScript autoloads from C#, it's just about accessing autoloads in general (usually in the same language, no interop, since most users use only one language for their whole project).

That code seems to suggest that a type named PlayerVariables should exist in my C# code [...]

That's correct, the documentation page assumes your autoload is also implemented in C#. Pretend that the image shows a path to the .cs file that defines the PlayerVariables type.

As far as I can tell, named classes in GDScript don't show up as types in C# so using GetNode<PlayerVariables>() can't possibly work.

Also correct, GDScript types are not available as C# types. This is also true for 3.x. To access GDScript instances from C#, use a less-specific type such as Godot.Node or Godot.Resource. For more information about how to interop between GDScript and C# see the Cross-language scripting documentation page.

[skyace65]

The issues with the C# code on this part of the page have been fixed over several PRs. The first C# example you mentioned with GetNode was removed in #8900. And the health example was removed in #7604 and replaced in #8852.