HN 표시: GYML – YAML 구문, JSON 의미 체계, 런타임 종속성 없음

YAML syntax. JSON semantics. Zero drama. YAML's spec contains 211 grammar productions across ten chapters. It has five scalar styles, five ways to write null, anchors, aliases, tags, and implicit type coercion rules that vary by implementation. The Norway Problem is a well-known example: NO is a valid YAML 1.1 boolean (False ), which surprises anyone using it as a country code or similar string value. GYML is a strict subset of YAML that trades that flexibility for predictability. It keeps YAML's block indentation syntax and applies JSON's type semantics: one spelling per type, no implicit coercion surprises, no anchors or tags. What you write is what you get. A strict subset of YAML. Everything valid GYML is also valid YAML. The reverse is absolutely not true, which is entirely the point. The rules fit on a sticky note: - One way to write each type. true /false for booleans.null for null. Decimal integers and floats. Double-quoted strings. Done. - Block style only. No flow mappings {a: 1} , no flow sequences[a, b] . Empty{} and[] are fine as explicit empty literals. - No dark arts. Anchors ( & ), aliases (* ), and tags (!! ) are rejected at the lexer. Your config file is not a program. - Duplicate keys are a hard error. Silent overwrites have caused too many bugs in too many codebases. - Strict indentation. Multiples of 2 spaces. Tabs rejected. No exceptions. # pip pip install gyml # uv (recommended) uv add gyml from gyml import loads config = loads(""" server: host: 0.0.0.0 port: 8080 debug: false workers: 4 """) print(config["server"]["port"]) # 8080 (int, not string) print(config["server"]["debug"]) # False (bool, not string) from gyml import load config = load("config.gyml") Both functions return plain Python objects: dict , list , str , int , float , bool , or None . No wrapper types. No schema required. What you see is what you get. Errors are precise. When something is wrong you get the exact line, column, and a message that tells you how to fix it, not a stack trace pointing at a C extension. from gyml import loads, ParseError try: loads("port: 0xFF") except ParseError as e: print(e) # line 1, col 7: "0xFF" -- hex/octal/binary literals are not allowed ParseError exposes three attributes: | Attribute | Type | Description | |---|---|---| message | str | Human-readable description of the violation | line | int | 1-based line number in the source | col | int | 1-based column number in the source | Convert any .gyml file to pretty-printed JSON: gyml config.gyml # pretty-print to stdout gyml config.gyml | jq '.server' # pipe into jq gyml config.gyml > out.json # write to file # All scalar types name: Alice age: 30 score: 9.5 active: true notes: null # Double-quoted strings preserve reserved words as strings status: "true" id: "404" # Nested mapping database: host: localhost port: 5432 ssl: true name: mydb # Sequence of scalars allowed_hosts: - localhost - 127.0.0.1 - 10.0.0.0 # Sequence of mappings (dash alone on its line, mapping indented below) users: - name: Alice role: admin - name: Bob role: viewer # Empty collection literals cache: {} tags: [] # Deeply nested is fine services: web: image: nginx ports: - 80 - 443 db: image: postgres env: POSTGRES_DB: mydb POSTGRES_USER: admin Every one of these is valid YAML. Every one of them has caused a real bug in someone's production system. | Input | Error | Why it's banned | |---|---|---| country: NO | not a valid boolean | Norway Problem; use "NO" | enabled: yes | not a valid boolean | use true | level: on | not a valid boolean | use true | value: ~ | not a valid null | use null | value: NULL | not a valid null | use null | port: 0xFF | hex/octal/binary not allowed | no implicit base conversion | ratio: .inf | .inf/.nan not allowed | not a JSON value | count: 1_000 | underscore separators not allowed | ambiguous in plain scalars | key: 'val' | single-quoted strings not allowed | one quoting style, double | true: val | boolean literals not allowed as keys | use "true" | a: 1\na: 2 | duplicate key | silent overwrites are bugs | key:\n | bare empty value | write null explicitly | data: &anchor val | anchors not allowed | configs aren't programs | ref: *anchor | aliases not allowed | configs aren't programs | obj: !!python/object | tags not allowed | absolutely not | # clone git clone https://github.com/janbjorge/gyml.git cd gyml # install deps (uv required) uv sync # run the tests uv run pytest # lint + format check uv run ruff check gyml/ tests/ uv run ruff format --check gyml/ tests/ # type-check uv run ty check gyml/ All four must pass clean before any change is considered done. Contributions are welcome. A few ground rules: - No runtime dependencies. The whole value proposition is zero deps. Don't add any third-party libraries. - No Any . The codebase is fully typed. Keep it that way. - Tests for everything. New behaviour gets a test. Bug fixes get a regression test. Use ok() ,ok_eq() , andfail() fromconftest.py . - Read AGENTS.md before touching anything.