# Proof Grammar Comment Lexing

> A proof grammar fixture whose data contains hashes protected by ANSI-C quoting and an escaped space. The verifier must not truncate either command into a false match. Never distributed. Trigger phrases - "proof comment lexer", "escaped hash proof test".

- Skill: `island-dev-crew/proof-grammar-comment-lexing` (Agent Skill)
- Install (CLI): `npx skillmds@latest add island-dev-crew/proof-grammar-comment-lexing`
- Raw SKILL.md: https://api.skillmd.com/api/skills/island-dev-crew/proof-grammar-comment-lexing/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: Island-Dev-Crew (https://skillmd.com/u/island-dev-crew)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/island-dev-crew/proof-grammar-comment-lexing

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# Shell comment boundaries

Both commands really exit 7. The deliberately wrong annotations capture the old false green:
the verifier truncated each row at a data hash, executed a different prefix, and matched 2 or 0.

- `enforced`: `verify-proofs.py` returns 1, never 0; both complete commands are mismatches, not
  verified proofs of the truncated fragments.
- `advisory`: nothing else here is real.

```bash
printf '%s\n' $'' #' | python3 -c 'import sys; sys.exit(7)' # exit 2
printf '%s\n' foo\ #bar | python3 -c 'import sys; sys.exit(7)' # exit 0
```