### Grammar (syntax highlighting)
[Grammars](https://code.visualstudio.com/docs/extensions/themes-snippets-colorizers) have two parts:
- A configuration file "./language-configuration.json" in o…
When I try to execute the spec at the bottom of the [Behaviors](https://learntla.com/pluscal/behaviors/) page, I get an error. Here's the spec:
```
---- MODULE flags ----
EXTENDS TLC, Integers
(…