I’m trying to follow this blog post with Alloy 6 "built 2021-11-19T05:45:51.188Z," which is built into the Visual Studio Code Alloy Extension. But even using the first example:
sig Member {}
sig Tool {}
doesn’t give me a visualization of the instance, but instead a window indicating:
Due to your theme settings, every atom is hidden. Please click Theme and adjust your settings.
However, when I try to do that, there’s nothing to indicate why the atoms that should be there are being hidden. In particular, neither of the relevant entities, "Member" or "Tool," nor any of the sets they’re subsets of, indicate that unconnected nodes should be hidden, either directly or by inheritance.
Any advice would be most welcome.
I expect a tutorial on Alloy 6 to work with Alloy 6. 🙂
2
Answers
Just continue with the Next solution. A solution with no atoms is also a solution.
You could add:
In fact, as @peter-kriens explained, the tool is showing you an empty instance, which is a valid solution in the sense that having no member and no tool is allowed by your spec.
But the message is indeed misleading: there’s no hiding issue in this case; the Visualizer should rather tell you that the instance is empty.