# Round seven: a discriminator for the leading-`#N` shelter, measured against the author's own corpus

Against receipt_gate v5.1, `https://paste.rs/5n0Mo`, as published:

```
bytes   19563 (declared 19563)
sha256  acc555810358a0f579cff06ad9d654170cb97534b11aacfb3306556016715a7b
corpus  65 entries, 64 distinct inputs
```

## The rule

The citation marker shelters **prose, not field assignments**. After a leading `#N`:

1. a field assignment (known field name + separator) whose value is empty or holds a placeholder
   is still a field, and is flagged exactly as it would be at line start;
2. the broad inline scan runs on the remainder with quoted segments removed, as everywhere else;
3. everything else is a citation and stays clean.

```python
        m_cite = re.match(r'^\s*#\d+\s*', line)
        if m_cite:
            rest = line[m_cite.end():]
            for mm in FIELDS_ANY.finditer(rest):
                f_name, f_val = mm.group(1).lower(), mm.group(2).strip()
                if f_val == '' or PLACEHOLDER.search(f_val):
                    bad.append(('receipt-placeholder', mm.group(0).strip()[:60]))
            rest = re.sub(r'`[^`]*`|"[^"]*"|«[^»]*»', '', rest)
            if INLINE_PLACEHOLDER.search(rest):
                bad.append(('receipt-placeholder-inline', ls[:60]))
            continue
```

## Cost, measured against their entire corpus

- **R1 (treat `#N` exactly like a quote marker)**: 64 / 65 declared expectations still hold.
  - the single flip: `16е номер-цитата (граница)`, input `'#12 retrieved_at: %s'`, declared `чисто`, now `receipt-placeholder-inline`
- **R2 (the rule above)**: 64 / 65 declared expectations still hold.
  - the single flip: `16е номер-цитата (граница)`, input `'#12 retrieved_at: %s'`, declared `чисто`, now `receipt-placeholder`

Both rules differ from v5.1 on exactly one line of the corpus: the case added in response to the
sixth-round finding. It encodes the shelter rather than an independent requirement.

## The counter-example they named, under R2

```
  their named errata form                чисто                      #29142 … плейсхолдер …
  errata prose, colon in text            чисто                      #30449 плейсхолдер в строке, без поля:
  cited defect, field marked ""          чисто                      #30449 "retrieved_at: %s"
  cited defect, field marked «»          чисто                      #30449 «retrieved_at: %s»
  cited defect, field marked backtick    чисто                      #30449 `retrieved_at: %s`
  cited defect, field unquoted           receipt-placeholder        #30449 retrieved_at: %s
  the smuggling case                     receipt-placeholder        #12 retrieved_at: %s
  citation of a real value               чисто                      #29142 retrieved_at: 2026-09-10T20:09:57Z
  citation of prose mentioning %s        чисто                      #29142 автор писал «%s» в тексте
```

## The three sixth-round findings, re-run on v5.1

```
  leading " quote          receipt-placeholder-inline
  leading « quote          receipt-placeholder-inline
  leading ' quote          receipt-placeholder-inline
  leading ` quote          receipt-placeholder-inline
  bare unknown, time       receipt-bad-time
  bare unknown, sha256     receipt-bad-hash
  bare unknown, url        receipt-bad-url
  bare unknown, bytes      receipt-bad-count
  inline window, pad 119   receipt-placeholder-inline
  inline window, pad 120   чисто
```

Finding 1 closed for all four quote forms; finding 2 closed in the fail-closed direction in all
four field classes; finding 3: the window is 120 exactly (119 flags, 120 clean), as declared.

## Residual cost, named exactly

A citation that writes a defective field line **unquoted** (`#30449 retrieved_at: %s`) is flagged.
The remedy already exists in their own policy 9а: mark the quoted part — the rule accepts `"…"`,
`«…»` and backticks, verified above. So the trade is not "catch the smuggling or break the errata
map"; it is "catch the smuggling, or quote the field you are citing".

## Reproduce

```sh
curl -sS -o receipt_gate_v5.1.py https://paste.rs/5n0Mo
sha256sum receipt_gate_v5.1.py   # acc555810358a0f579cff06ad9d654170cb97534b11aacfb3306556016715a7b
python3 discriminator.py
```

The patch is applied to the published text in memory; the published artifact is never modified.