fix: make TextMate grammar regexes compatible with Joni/TM4E#113
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jgsuess wants to merge 1 commit intoFHIR:masterfrom
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fix: make TextMate grammar regexes compatible with Joni/TM4E#113jgsuess wants to merge 1 commit intoFHIR:masterfrom
jgsuess wants to merge 1 commit intoFHIR:masterfrom
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The FSH TextMate grammar uses several regex patterns that are incompatible with the Joni regex engine (Java port of Oniguruma) used by Eclipse TM4E. These patterns work in VS Code's Oniguruma but fail silently in Joni, causing syntax highlighting to break. Fixes: - Remove nested variable-length lookbehind (?<=\bfrom\s*) in keywords pattern — `system` is now matched as a plain reserved keyword - Replace (?=\s)\b with (?=\s|$) in keywords, booleans patterns so tokens at end-of-line are matched (e.g. `* name 1..* MS`) - Replace (?=[\s,])\b with (?=[\s,]|$) in numbers pattern for same reason - Replace \b with (?=\s|$) in cardinality pattern — \b fails after non-word char `*` (e.g. `1..*` was not highlighted) - Move \s* outside lookbehind in insert RuleSet bracket pattern — variable-length content inside (?<=...) is not supported All patterns now use only fixed-length lookbehinds, which is the common subset supported by Oniguruma (VS Code), Joni (Eclipse TM4E), and JetBrains regex engines. No change in VS Code behavior.
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Summary
The FSH TextMate grammar uses several regex patterns that are incompatible with the Joni regex engine (Java port of Oniguruma) used by Eclipse TM4E. These patterns work in VS Code's Oniguruma but fail silently in Joni, causing syntax highlighting to break entirely or miss tokens at end-of-line.
Changes (5 patterns, 5 lines changed)
(?<=\bfrom\s*);systemis now a plain reserved keyword(?=\s)\b→(?=\s|$)so tokens likeMSat end-of-line are matched\s*outside lookbehind (variable-length content inside(?<=...)not supported)(?=\s)\b→(?=\s|$)for end-of-line matching(?=[\s,])\b→(?=[\s,]|$)for end-of-line matching\b→(?=\s|$)because\bfails after non-word char*(e.g.1..*)Compatibility
All patterns now use only fixed-length lookbehinds — the common subset supported by:
Testing
Tested in Eclipse 2026-03 with TM4E 0.17.2. Before: no syntax highlighting (regex parse errors on every line). After: full keyword, string, comment, number, and cardinality highlighting.
No change in VS Code behavior — Oniguruma is a superset of the patterns used here.