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Implements decorator `nested` that adds a parent and children to a dataclass.

Project description


Implements decorator nested that adds a parent and children to a dataclass.

Both parent and child class should be decorated with nested.


Example usage of the parent attribute on a nested dataclass:

from dataclasses import dataclass
from typing import List

from nested_dataclasses import nested

class TextCount:
    text: str
    count: int

    def fraction(self):
        return self.count / self.parent.total_count

class TextCounts:
    counts: List[TextCount]

    def total_count(self):
        return sum(count.count for count in self.counts)

hello = TextCount("hello", 3)
hi = TextCount("hi", 1)
counts = TextCounts([hello, hi])




We can be installed with:

pip install nested-dataclasses

Development installation of this project itself

We're installed with pipenv, a handy wrapper around pip and virtualenv. Install that first with pip install pipenv. Then run:

PIPENV_VENV_IN_PROJECT=1 pipenv install --python 3.8 --dev

In case you do not have python 3.8 on your machine, install python using pyenv and try the previous command again. See install pyenv below for instructions.

In order to get nicely formatted python files without having to spend manual work on it, run the following command periodically:

pipenv run black nested_dataclasses

Run the tests regularly. This also checks with pyflakes, black and it reports coverage. Pure luxury:

pipenv run pytest

If you need a new dependency (like requests), add it in in install_requires. Afterwards, run install again to actually install your dependency:

pipenv install --dev


Pipenv installs zest.releaser which allows you to release the package to a git(hub) repo. It has a fullrelease command that asks you a few questions, which you all respond to with <enter>:

pipenv run fullrelease

Install pyenv

We can install pyenv by running the following commands:

sudo apt-get install -y make build-essential libssl-dev zlib1g-dev libbz2-dev libreadline-dev libsqlite3-dev wget curl llvm libncurses5-dev libncursesw5-dev xz-utils tk-dev libffi-dev liblzma-dev
curl -L | bash

Also make sure to put pyenv in your .bashrc or .zshrc as instructed by the previous commands.

Changelog of nested-dataclasses

0.1 (2020-06-08)

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