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FA-3566 / Lexical grammars / Open access

A priority marker rejects allowed internal whitespace · case 01

A priority marker rejects allowed internal whitespace.

Verified by executionVariant 1 · 4 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The recognizer uses '!important', which admits or omits a token shape forbidden by the stated grammar.

VERIFIED REPAIR

Implement the complete stated contract, including the boundary fixtures: Accept exclamation, optional ASCII whitespace, and lowercase important.

Unsuccessful approach: The candidate grammar '! *important' still disagrees with the explicit boundary fixtures.

Case contract

Accept exclamation, optional ASCII whitespace, and lowercase important.

Why this case matters

A local executable model for consumers of structured text; oracle values are authored literals, not outputs copied from the repaired implementation.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct
from urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit
from email.header import decode_header, make_header
from email.utils import getaddresses
from xml.etree import ElementTree as ET
import shlex, string, textwrap

N = 1
observations = []
def solve(x):
    try:
        return bool(re.fullmatch('!important',x))
    except Exception as exc:
        return {"error": type(exc).__name__}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('boundary 1', solve('!\timportant'), True)
check('boundary 2', solve('! important'), True)
check('boundary 3', solve('!important'), True)
check('boundary 4', solve('important'), False)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
boundary 1FalseTrueFailed
boundary 2FalseTrueFailed
boundary 3TrueTruePassed
boundary 4FalseFalsePassed

SHA-256 / 378049a48807a8c1b6cfef5249abd6818e394ca5b4df69287fc1438396889d54

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct
from urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit
from email.header import decode_header, make_header
from email.utils import getaddresses
from xml.etree import ElementTree as ET
import shlex, string, textwrap

N = 1
observations = []
def solve(x):
    try:
        return bool(re.fullmatch('! *important',x))
    except Exception as exc:
        return {"error": type(exc).__name__}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('boundary 1', solve('!\timportant'), True)
check('boundary 2', solve('! important'), True)
check('boundary 3', solve('!important'), True)
check('boundary 4', solve('important'), False)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
boundary 1FalseTrueFailed
boundary 2TrueTruePassed
boundary 3TrueTruePassed
boundary 4FalseFalsePassed

SHA-256 / 2537a3e86e34c3cf1896309fd286c37977be362513d78d9adf4e7645e1f97641

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct
from urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit
from email.header import decode_header, make_header
from email.utils import getaddresses
from xml.etree import ElementTree as ET
import shlex, string, textwrap

N = 1
observations = []
def solve(x):
    try:
        return bool(re.fullmatch('![ \\t\\r\\n]*important',x))
    except Exception as exc:
        return {"error": type(exc).__name__}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('boundary 1', solve('!\timportant'), True)
check('boundary 2', solve('! important'), True)
check('boundary 3', solve('!important'), True)
check('boundary 4', solve('important'), False)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
boundary 1TrueTruePassed
boundary 2TrueTruePassed
boundary 3TrueTruePassed
boundary 4FalseFalsePassed

SHA-256 / 1a7e6a1c3c1e10cf915f2db24685e513ab034d9366384dfe661c70e13aa44547

Verification & scope

This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:37:27.603289+00:00.

Case digest / 298de8b4c9382c688ab10b2917f1614ebfcff0c1a172ff38b63ce8ce1ddef2da