Metadata-Version: 2.3
Name: python-none-objects
Version: 1.1.4
Summary: Add more constant "None" objects to Python to avoid boilerplate code
Project-URL: Homepage, https://github.com/LLyaudet/python-none-objects
Project-URL: Bug Tracker, https://github.com/LLyaudet/python-none-objects/issues
Author-email: Laurent Lyaudet <laurent.lyaudet@gmail.com>
License: GNU LESSER GENERAL PUBLIC LICENSE
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License-File: COPYING
License-File: COPYING.LESSER
Keywords: Default values,Immutable,None,Python
Classifier: License :: OSI Approved :: GNU Lesser General Public License v3 or later (LGPLv3+)
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 3
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Description-Content-Type: text/markdown

# python-none-objects

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|     **A collection of "None" objects compatible with various Python types**     |

The following code yields warning for "Default argument value is mutable".

```python3
from typing import List, Dict

def foo(some: int, other: List = [], thing: Dict = {}):
    for o in other:
        bar(some, o, thing)
```

It is usually recommended to use None instead
(<https://stackoverflow.com/questions/41686829/why-does-pycharm-warn-about-mutable-default-arguments-how-can-i-work-around-the>):

```python3
from typing import List, Dict, Optional

def foo(some: int, other: Optional[List] = None, thing: Optional[Dict] = None):
    if other is None:
        other = []
    if thing is None:
        thing = {}
    for o in other:
        bar(some, o, thing)
```

But I prefer less boilerplate code like this:

```python3
from typing import Iterable, Mapping
from types import MappingProxyType

def foo(some: int, other: Iterable = (), thing: Mapping = MappingProxyType({})):
    for o in other:
        bar(some, o, thing)
```

This package introduces constants to make the code more readable:

```python3
from typing import Iterable, Mapping
from python_none_objects import NoneIterable, NoneMapping

def foo(some: int, other: Iterable = NoneIterable, thing: Mapping = NoneMapping):
    for o in other:
        bar(some, o, thing)
```

Be sure to look at the discussions on GitHub:
<https://github.com/LLyaudet/python-none-objects/discussions>.

There is a poll on the naming convention you would prefer:
<https://github.com/LLyaudet/python-none-objects/discussions/2>.

And there is a discussion on various ideas to optimize the code with these constants:
<https://github.com/LLyaudet/python-none-objects/discussions/3>.

I think it would be better to have this kind of constants in the standard library.
If you think after reading everything, that it is indeed a good idea,
add a star to this repository to let the rest of the Python community know
that you would like to see such constant objects in the language :).
<https://github.com/LLyaudet/python-none-objects/>
If the project gains popularity, I'll try to propose it officially.

[pypi-version]: https://img.shields.io/pypi/v/python-none-objects.svg
[pypi]: https://pypi.org/project/python-none-objects/
