Mark anchor missing "_" prefix
Auto-fixAudit code: anchor-naming-mark-no-prefix
Definition
GPOS mark-positioning convention: marks (combining diacritics) carry anchors prefixed with "_" so they pair up with same-named base anchors. Without the prefix, this anchor never enters the mark feature.
How Patens surfaces this
The Patens audit module checks for anchor-naming-mark-no-prefix across five teaching surfaces: the edit-panel inline issue list, the
project-wide audit page, the release pre-flight check, the family hub,
and the home-page project tile. Every surface shows the same plain-English
explanation and links back to this page. This rule has a one-click Fix button in
the editor — the audit module both detects the issue and applies a
deterministic correction with a labelled snapshot, so the ⌘Z path back is preserved.
Run this check yourself
Patens runs every audit rule live as you draw — including this one.
The editor (in private alpha) shows anchor-naming-mark-no-prefix firing on real
glyphs, or check your own work from the CLI:
npx patens audit your-project.font.jsonCanonical references
Primary literature where this rule is established or explained. Drawn from the open-licensed corpus — browse the full 42-source canonical library or read the research artifact.
- Adobe OpenType Feature File Specification ↗
Adobe Type Tools · 2005 · Adobe Systems· § Mark-to-base, naming conventions
Anchor names on mark glyphs require an underscore prefix (_top, _bottom) per the standard convention; without it, the GPOS lookup fails to bind.