rohitg00/ai-engineering-from-scratch · error · ValueError

rule {r.get('name')} missing substring or regex

Error message

rule {r.get('name')} missing substring or regex

What it means

Error "rule {r.get('name')} missing substring or regex" thrown in rohitg00/ai-engineering-from-scratch.

Source

Thrown at phases/19-capstone-projects/83-prompt-injection-detector/code/main.py:135

    score = sum(1 for w in words if w in _COMMON_WORDS)
    if score >= 2:
        return text + " " + candidate
    return text


class Detector:
    def __init__(self, rules: Iterable[dict[str, object]] | None = None) -> None:
        rules_list = list(rules) if rules is not None else all_rules()
        self.substring_rules: list[dict[str, object]] = []
        self.regex_rules: list[dict[str, object]] = []
        for r in rules_list:
            if "substring" in r:
                self.substring_rules.append(r)
            elif "regex" in r:
                compiled = re.compile(str(r["regex"]), re.IGNORECASE | re.DOTALL)
                self.regex_rules.append({**r, "_compiled": compiled})
            else:
                raise ValueError(f"rule {r.get('name')} missing substring or regex")

    def analyze(self, prompt: str) -> Verdict:
        normalized = normalize(prompt)
        haystacks = (prompt.lower(), normalized)
        scores_by_category: dict[str, float] = {}
        fired: list[str] = []
        for r in self.substring_rules:
            needle = str(r["substring"]).lower()
            if any(needle in h for h in haystacks):
                cat = str(r["category"])
                score = float(r["score"])
                scores_by_category[cat] = max(scores_by_category.get(cat, 0.0), score)
                fired.append(str(r["name"]))
        for r in self.regex_rules:
            compiled: re.Pattern = r["_compiled"]
            if any(compiled.search(h) for h in haystacks):
                cat = str(r["category"])
                score = float(r["score"])

View on GitHub (pinned to 39ea8a1c6d)

When it happens

Trigger: Thrown at phases/19-capstone-projects/83-prompt-injection-detector/code/main.py:135 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of rohitg00/ai-engineering-from-scratch@39ea8a1c6d (2026-08-26). Data as JSON: /api/errors/bf1995a865a9c1fc. Report an issue: GitHub.