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Comment by robochat | Hacker News Reader

Relative imports used to work much more naturally IMHO in python2 but then they broke it in python3 because Guido wanted scripts and modules to always be separate codebases. So, whereas it used to be easy to have a module that could also be run as a script inside a package, this is now very difficult to implement. To the extent that any python2 code that does this, should probably be refactored when being ported to python3.

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This decision has bit me in the ass so often.

I want to organize my code logically in directories. As a script grows, I want the ability to spin out parts of that file to separate files.

In order to do that in python, I need separate directories between the script and the spun-out functionality. This ends with a script that says "do function from module" and all code being in the module.

Having code in different directories for no reason except "the import system" sucks. How is this supposed to go?

FWIW, my command-line tools and any support code are all in a subdirectory under my package directory.

I used to include a simple stub Python program (~10 lines) as a "script" in my setup.py that would import the right code and call it.

Then I learned that "entry_points" implemented most of the dispatch behavior I wanted.

I no longer have those scripts, just an entry that basically says "from abc.cli.prog1 import main; main()". The prog1.py, prog2.py, etc. look like normal command-line scripts, assuming the usual:

    if __name__ == "__main__":
        main()

The major downside is I can't suppress SIGPIPE and SIGINT until main() is called, leaving a wider window where something like ^C gives a unwanted Python stack trace.

So as your script grows, don't you eventually rename it to whatever/__main__.py and run it with -m? seems like a fairly trivial transform that then allows you to spin out as many modules as you need.

Are you sure you're not confusing changes to the import system with changes to the default sys.path (especially when executing a file)?

Because unless I'm missing something, the changes to the import system make this more reliable, not less: in Python 2, implicitly relative imports means `import x` might depend on the file's location. In Python 3, it does not, it depends solely on the setup of the sys.path.

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