#255: Closember eve, the cure for Hacktoberfest?

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Special guest: Will McGugan

Michael #1: Wrapping C++ with Cython

• By Anton Zhdan-Pushkin
• A small series showcasing the implementation of a Cython wrapper over a C++ library.
• C library: yaacrl - Yet Another Audio Recognition Library is a small Shazam-like library, which can recognize songs using a small recorded fragment.
• For Cython to consume yaacrl correctly, we need to “teach” it about the API using `cdef extern
• It is convenient to put such declarations in *.pxd files.
• One of the first features of Cython that I find extremely useful — aliasing. With aliasing, we can use names like Storage or Fingerprint for Python classes without shadowing original C++ classes.
• Implementing a wrapper: pyaacrl - The most common way to wrap a C++ class is to use Extension types. As an extension type a just a C struct, it can have an underlying C++ class as a field and act as a proxy to it.
• Cython documentation has a whole page dedicated to the pitfalls of “Using C++ in Cython.”
• Distribution is hard, but there is a tool that is designed specifically for such needs: scikit-build.
• PyBind11 too

Brian #2: tbump : bump software releases

• suggested by Sephi Berry
• limits the manual process of updating a project version
• tbump init 1.2.2 initializes a tbump.toml file with customizable settings
  • --pyproject will append to pyproject.toml instead
• tbump 1.2.3 will
  • patch files: wherever the version listed
  • (optional) run configured commands before commit
    • failing commands stop the bump.
  • commit the changes with a configurable message
  • add a version tag
  • push code
  • push tag
  • (optional) run post publish command
  • Tell you what it’s going to do before it does it. (can opt out of this check)
• pretty much everything is customizable and configurable.

• I tried this on a flit based project. Only required one change

      # For each file to patch, add a [[file]] config
      # section containing the path of the file, relative to the
      # tbump.toml location.
      [[file]]
      src = "pytest_srcpaths.py"
      search = '__version__ = "{current_version}"'
  

• cool example of a pre-commit check:

      #  [[before_commit]]
      #  name = "check changelog"
      #  cmd = "grep -q {new_version} Changelog.rst"
  

Will #3: Closember by Matthias Bussonnier

Michael #4: scikit learn goes 1.0

• via Brian Skinn
• The library has been stable for quite some time, releasing version 1.0 is recognizing that and signalling it to our users.
• Features:
• Keyword and positional arguments - To improve the readability of code written based on scikit-learn, now users have to provide most parameters with their names, as keyword arguments, instead of positional arguments.
• Spline Transformers - One way to add nonlinear terms to a dataset’s feature set is to generate spline basis functions for continuous/numerical features with the new SplineTransformer.
• Quantile Regressor - Quantile regression estimates the median or other quantiles of Y conditional on X
• Feature Names Support - When an estimator is passed a pandas’ dataframe during fit, the estimator will set a feature_names_in_ attribute containing the feature names.
• A more flexible plotting API
• Online One-Class SVM
• Histogram-based Gradient Boosting Models are now stable
• Better docs

Brian #5: Using devpi as an offline PyPI cache

• Jason R. Coombs
• This is the devpi tutorial I’ve been waiting for.

• Single machine local server mirror of PyPI (mirroring needs primed), usable in offline mode.

      $ pipx install devpi-server
      $ devpi-init
      $ devpi-server
  

• now in another window, prime the cache by grabbing whatever you need, with the index redirected

      (venv) $ export PIP_INDEX_URL=http://localhost:3141/root/pypi/
      (venv) $ pip install pytest, ...
  

• then you can restart the server anytime, or even offline

       $ devpi-server --offline
  

• tutorial includes examples, proving how simple this is.

Will #6: PyPi command line

Extras

Brian:

• I’ve started using pyenv on my Mac just for downloading Python versions. Verdict still out if I like it better than just downloading from pytest.org.
• Also started using Starship with no customizations so far. I’d like to hear from people if they have nice Starship customizations I should try.
• vscode.dev is a thing, announcement just today

Michael:

• PyCascades Call for Proposals is currently open
• Got your M1 Max?
• Prediction: Tools like Crossover for Windows apps will become more of a thing.

Will:

• GIL removal
  • https://docs.google.com/document/u/0/d/18CXhDb1ygxg-YXNBJNzfzZsDFosB5e6BfnXLlejd9l0/mobilebasic?urp=gmail_link
  • https://lwn.net/SubscriberLink/872869/0e62bba2db51ec7a/
• vscode.dev

Joke:

• The torture never stops
• IE (“Safari”) Eating Glue