Python allows programmers to pass additional arguments to functions via comments. Now armed with this knowledge head out and spread it to all code bases.

Feel free to use the code I wrote in your projects.

Link to the source code: https://github.com/raldone01/python_lessons_py/blob/v2.0.0/lesson_0_comments.ipynb

Image transcription:

# First we have to import comment_arguments from arglib
# Sadly arglib is not yet a standard library.
from arglib import comment_arguments


def add(*args, **kwargs):
    c_args, c_kwargs = comment_arguments()
    return sum([int(i) for i in args + c_args])


# Go ahead and change the comments.
# See how they are used as arguments.

result = add()  # 1, 2
print(result)
# comment arguments can be combined with normal function arguments
result = add(1, 2)  # 3, 4
print(result)

Output:

3
10

This is version v2.0.0 of the post: https://github.com/raldone01/python_lessons_py/tree/v2.0.0

Note:

v1.0.0 of the post can be found here: https://github.com/raldone01/python_lessons_py/tree/v1.0.0

Choosing lib as the name for my module was a bit devious. I did it because I thought if I am creating something cursed why not go all the way?

Regarding misinformation:

I thought simply posting this in programmer humor was enough. Anyways, the techniques shown here are not yet regarded best practice. Decide carefully if you want to apply the shown concepts in your own code bases.

  • drathvedro@lemm.ee
    13·
    1 month ago

    I hate this shit being routinely used in PHP. Symfony uses those functional comments for routing, essentially scanning every controller file as text on every visit, to gather the url patterns above functions. Laravel uses Reflection, which is functionally the same thing, to provide arguments to controller functions. Also, kind of related, the project I’m working now has few functions that use backtrace to return different results based on where they are called from. It is indeed very cursed and I’m ripping out any usages of them whenever I see one.

    • piccolo@sh.itjust.works
      4·
      1 month ago

      Comment Annotations were a nessecary thing as php did not support a native way to do it. However, since php 8, there is now native attributes.

    • ByteOnBikes@slrpnk.net
      8·
      1 month ago

      It’s actually kind of nice to see this as a JS developer.

      Not like, “Oh wow this is neat!”

      But like, “Finally the golden child, Python, also has some fucked up shit”

  • davel [he/him]@lemmy.mlEnglish
    12·
    1 month ago

    What? There is no lib module.

    $ python3.13 -c 'import lib'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
    import lib
ModuleNotFoundError: No module named 'lib'
$
  • would_be_appreciated@lemmy.mlEnglish
    69·
    1 month ago

    I assume the people freaking out about how dumb python is didn’t bother to read the code and have never coded in python in their life, because the behavior here is totally reasonable. Python doesn’t parse comments normally, which is what you’d expect, but if you tell it to read the raw source code and then parse the raw source code for the comments specifically, of course it does.

    You would never, ever accidentally do this.

    …you’d also never, ever do it on purpose.

    • Swedneck@discuss.tchncs.de
      25·
      1 month ago

      yeah frankly this post is borderline misinformation, they specifically import a library to read comments as arguments, it’s like redefining keywords in C and complaining about C being dumb

        • bastion@feddit.nl
          4·
          1 month ago

          Yeah. ‘lib’ isn’t a standard Python library, it’s the name of the abomination that this person created. Since python has quite a bit of useful introspection, they can do something like:

          • get the stack
          • find the exact call to abomination.add()
          • reparse the text of that line, turn the text of the comment into actual numbers, and add them

          Now, I don’t know if python keeps the comments around, so it may involve getting the filename and line number, reading the file, and manually extracting the comment text from that line.

          • CanadaPlus@lemmy.sdf.org
            4·
            1 month ago

            It’s not even actually called lib. The line just straight up isn’t in the image “transcribed”, and it’s from arglib import comment_arguments in the original code.

            Yeah, I gave this one a downvote.

            • raldone01@lemmy.worldOPEnglish
              2·
              1 month ago

              I updated the source after this post was made. The image transcription still holds. I did not update the image and the post text.

              You can view the git history. I will tag the specific commit at the time of the post later and update it accordingly.

              • CanadaPlus@lemmy.sdf.org
                2·
                1 month ago

                Ah, and you’re the author. That kind of changes the whole context here.

                It doesn’t mean much, but have your upvote back.

    • Chais@sh.itjust.works
      22·
      1 month ago

      You can so stupid shit in any language. I admit Python doesn’t exactly make it difficult. A bit like JS, but different.

      • verdigris@lemmy.ml
        85·
        1 month ago

        Being able to get the line number is very different from comments being parsed.

        Edit: didn’t realize this was custom code built to be cursed.

        • bjorney@lemmy.ca
          17·
          1 month ago

          You should look at how OPs example works first maybe

          The python interpreter isn’t parsing comments, the add() function is just getting the current line number from the call stack context, and using a regex to spit out the numbers to the right of the “#” on the current executing line of the source code.