A naive implementation of C3 linearization algorithm used in Python's MRO
C3 Linearization Algorithm
c3linear is a naïve implementation of
C3 linearization algorithm.
It's used in Python 2.3+ for Method Resolution Order.
See Raymond Hettinger's Python’s super() considered super! for more information.
The recursive implementation can be found at
It used an auxiliary function
_merge as well as a bunch of classes
to help with algorithm's readability.
The project's come to life as a byproduct of debugging an overcomplicated hierarchy of mixin classes. I thought I knew how exactly MRO is computed, but it turned out I didn't.
I've tried to keep the code idiomatic and easy to follow at the expense of performance. The project is really took a couple of hours to complete. Although I didn't care about time complexity and didn't check correctness as thoroughly as I should, I think the project may help someone who want to learn how Python's Method Resolution Order works.
- Get the code and install it with
python setup.py install(Python 3.6+ required)
from c3linear.mro import mro
- Check against built-in MRO:
>>> class A: pass >>> class`B(A): pass >>> mro(B) == B.mro() True
Take a look at
tests for more examples.
- Install dependencies:
pip install -e .
- (Optional) Install extra packages:
pip install -e .[extra]
- Run tests with:
python setup.py test
flake8for PEP8 compliance testing:
python setup.py flake8
If you've found a bug, please open an issue describing the problem first.
The project is licensed under MIT License. For further information see
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