All 3 remaining known constraints resolved. CLAUDE.md now shows zero.
1. CDX compound index WRITE support (was read-only)
New file: hbrdd/cdx/build.go (~400 LOC)
- CreateOrAddTag() builds Harbour-compatible CDX files
- Bit-packed leaf pages (RecBits/DupBits/TrlBits compression)
- Interior nodes with big-endian RecNo/ChildPage
- Compound root directory (structural B-tree of tag names)
- Append-safe: preserves existing tags when adding new ones
- Linked leaf pages (LeftPtr/RightPtr for sequential scan)
Pipeline: INDEX ON expr TAG tagname TO file
- ast.IndexCmd gains TagName field
- Parser captures TAG name (was discarded)
- gengo passes TagName to OrderCreateParams
- indexer.go routes to cdx.CreateOrAddTag when TAG specified
Verified: 3 tags (BYNAME/BYCITY/BYAGE), OrdSetFocus by name,
SEEK, GoTop/GoBottom, close+reopen with SET INDEX TO
2. {||} empty code block parsing in function arguments
Parser's parseArrayOrBlock() called parseExpr() unconditionally
after closing |, failing when body was empty ({||}).
Fix: check for RBRACE after closing | and emit NIL literal body.
{=>} empty hash already worked.
3. Semicolon IF...ENDIF — already worked (removed from constraints)
Tests:
go test ./... 14 packages ALL PASS
FiveSql2 43/43 100%
compat_harbour 51/51
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>