Or ( || ) removes syntax-highlighting

[MathiasSJacobsen]

When using "||" in a rule, the syntax-highlighting disappears from on every lower (<=) level rules.

Langium version: 0.2.0

Steps To Reproduce

1. Create a new grammar.
2. Define a rule that contains "||" name=ID .
3. Define a rule that contains "let" name=ID.
4. Then define an other rule that contains multiple of the first rule and second rule:

   OtherRule:  
   "component" name=ID "{"
   ruleOnes+=RuleOne*
   ruleTwos+=RuleTwo*
   "}"

5. Then run the plugin and try to make the grammar. Now the syntax-highlighting should only appear on the first line.

Link to code example: https://pastebin.com/CKcXgezy

The current behavior

Her you can see that let is not purple.

The expected behavior

[msujew]

Hey, @MathiasSJacobsen thanks for the report.

Do you mind testing whether this is the same issue as described in here: https://github.com/langium/langium/discussions/349?

If it is fixed by adding the appropriate \ in the tmLanguage.json file, then this issue has already been fixed with #293 and will release in 0.3 (this month).

[MathiasSJacobsen]

Hi, @msujew.

I don't think this is the same problem, or at least I can't seem to see that it is 😅.

This is the same line as mentioned in #349 and there isn't missing any \\.

"match": "(\\;|\\{|\\}|\\||)"

I guess the problem is that the second | in the \\||.

If you want to make a language able to say:

if (…… || ……) {
    …
}

[msujew]

@MathiasSJacobsen thanks for sharing the generated code, because there actually is an error in there. The \\|| should actually be \\|\\|. Just \\|| is a combination of an escaped | and a regex alternative. Can you try manually adding the second \\?

[MathiasSJacobsen]

I'm so sorry yes that worked. Didn't work late last night. Probably forgot to regenerate. Then I can't wait for the new release!