baseclasses 0.1.1

Description:

baseclasses 0.1.1

baseclasses
Simple dataclasses alternative (beta)



Installation
baseclasses is available on PyPI:
pip install baseclasses

Quick Start
baseclasses is an alternative to dataclasses.
There are many such alternatives, and there are a lot of reasons
to use them (including the built-in
dataclasses), but if you want a library with:

No monkey-patched methods generated from strings
No special decorators, just regular inheritance
Ability to order fields in subclasses as desired
Auto-inheritance of parent properties, with ability to change per subclass
Emphasis on keyword args over positional args
Optional __pre_init__ ability to mutate kwargs
Optional ability to reference other kwargs in default_factory func
A shorthand helper to specify InternalStateField
Ability to differentiate between str and repr

you can give baseclasses a try. E.g.:
from typing import Dict, Optional

import baseclasses


# No decorator
class Foo(baseclasses.FrozenBaseClass):
a: int
b: int
c: Optional[str] = baseclasses.Field(default="hello", hash=False)
_d: Dict = baseclasses.InternalStateField(default_factory=dict)


# Auto-inherits FrozenBaseClass properties
class ChildFoo(Foo):
# No problems with child class field ordering
x: float

# Dynamic defaults
y: int = baseclasses.Field(
default_factory=lambda **kwargs: kwargs["a"] * 2.0
)


# Override frozen state per child class
class MutableChildFoo(ChildFoo, frozen=False):
pass

Comparisons to Alternatives
See tests/test_compare.py.
Like dataclasses, but:

No issues with adding new optional fields because you're forced to
use kwargs in all but the simplest cases
Uses metaclass and simple inheritance over monkey-patched generated code
Child classes automatically inherit state from parent,
so no need to re-declare
But you can also change frozen status per child class
You can use default_factory(lambda **kwargs: ...) to access init fields
Or you can mutate kwargs with an optional __pre_init__
More consistent with traditional OOP style
(e.g., obj.get_fields() instead of dataclasses.get_fields(obj))

Like dataclassy but:

Uses metaclass and simple inheritance over monkey-patched generated code

There are others:

attrs
pydantic
traitlets
param

Note: there are perfectly valid reasons
for why the Python community
decided to use generated code over simple inheritance.
baseclasses is just an alternative that implements things differently.
TODO

Add init property to field (to mirror dataclasses)
Expose obj.replace(**kwargs) (to mirror dataclasses)
Consider serialize property to field
Take advantage of PEP 681 included in Python 3.11