https://github.com/likeinlife/light-types

Create types that respect the invariant. "Parse, don't validate"
https://github.com/likeinlife/light-types

phantom-types python3 types value-object

Last synced: 4 months ago
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Create types that respect the invariant. "Parse, don't validate"

• Host: GitHub
• URL: https://github.com/likeinlife/light-types
• Owner: likeinlife
• License: mit
• Created: 2024-07-26T15:28:46.000Z (over 1 year ago)
• Default Branch: main
• Last Pushed: 2024-08-16T20:36:10.000Z (over 1 year ago)
• Last Synced: 2025-09-11T05:14:19.425Z (5 months ago)
• Topics: phantom-types, python3, types, value-object
• Language: Python
• Homepage:
• Size: 38.1 KB
• Stars: 2
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

          
# Light Types

[![image](https://img.shields.io/pypi/v/light-types.svg)](https://pypi.python.org/pypi/light-types)

[![codecov](https://codecov.io/gh/likeinlife/light-types/graph/badge.svg?token=7QUSPNC4CQ)](https://codecov.io/gh/likeinlife/light-types)

[![Rye](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/astral-sh/rye/main/artwork/badge.json)](https://rye.astral.sh)

[![image](https://img.shields.io/pypi/l/light-types.svg)](https://github.com/likeinlife/light-types/blob/main/LICENSE)



[![Ruff](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/astral-sh/ruff/main/assets/badge/v2.json)](https://github.com/astral-sh/ruff)

[![image](https://img.shields.io/pypi/pyversions/light-types.svg)](https://pypi.python.org/pypi/light-types)

"Parse, don't validate"

Compatible with PydanticV2

Inspired by [Phantom types](https://github.com/antonagestam/phantom-types/)

# Examples

## Sample

```python

from light_types import LightType

class StartsWithString(str, LightType):

    @classmethod

    def validate(cls, value: str) -> bool:

        return value.startswith("String")

```

## With Pydantic

```python

from light_types import LightType

class StartsWithString(str, LightType):

    @classmethod

    def validate(cls, value: str) -> bool:

        return value.startswith("String")

class MyModel(BaseModel):

    value: StartsWithString

assert TypeAdapter(MyModel).validate_python({"value": "StringOk"})

```

## QLightType

```python

from light_types import QLightType, NumericQ

class NumericBetween5And10(int, QLightType):

    validator = (NumericQ() > 5).custom(lambda n: n < 10)

```

```python

from light_types import QLightType, StringQ

class StartsWithString(str, QLightType):

    validator = StringQ().startswith("String")

```

```python

from light_types import QLightType, StringQ

class StringWith2O(str, QLightType):

    validator = StringQ().startswith("String") & StringQ().custom(lambda s: s.count("o") >= 2)

```

```python

from light_types import QLightType, StringQ

class StringWith2O(str, QLightType):

    validator = StringQ().startswith("String") | ~StringQ().custom(lambda s: s.count("o") >= 2)

```

```python

from light_types import QLightType, StringQ, LengthQ

class StringWith2O(str, QLightType):

    validator = StringQ().startswith("foo") & (LengthQ[str]() > 5)

```

# Tests, linting, formatting

- `rye test | lint | fmt`