Distinguish fragments from rule calls

[Lotes]

It is a minor thing. When you use fragments, they do not distinguish from rule calls. So, when you review a grammar on first sight you think a naked rule call is missing an assignment... but actually it is a fragment call with assignments in it.

My proposal is to either highlight it with a special color, or to have a separate syntax, like @fragmentName.

WDYT?

[montymxb]

I've wondered a bit about this too. I would think a slight color or syntax change could help, but nothing too great. For reference, here's how a fragment shows up in relation to a parser rule currently. It might also be nice when one hovers over the usage that you could see the associated description of Fragment or ParserRule infers .... In such a way you could hover over the components to identify what they are.

[spoenemann]

I wouldn't change the syntax because a parser rule can be without assignment as well (unassigned rule call, see also #205). But using a special color using semantic tokens sounds good.

[Lotes]

Added an issue. Sorry for forgetting this thread ^^*