this post was submitted on 21 Nov 2024
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Programmer Humor

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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.

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[–] [email protected] 45 points 4 days ago (4 children)

This does not actually work, right? Right?

[–] [email protected] 52 points 4 days ago* (last edited 4 days ago) (1 children)

The add() function (that is available in the source code) basically uses some built in debugging tools to find out where in the code the function is called, and then parses the comment from the file and uses it for adding stuff.

I’ve never tried (becuse why would you…) but something similar can probably be built in any interpreted language

It’s not something Python does by design

[–] [email protected] 10 points 4 days ago* (last edited 4 days ago) (4 children)

Thanks :) ! Could you tell me what use case/purpose such function can have from a dev perspective?

[–] [email protected] 10 points 3 days ago

This stuff is normally used for creating human readable error messages. E.g. printing the line of your code that actually set off the exception

[–] [email protected] 8 points 4 days ago* (last edited 4 days ago) (1 children)

This specific use case? To make a meme, mainly ¯\(ツ)

As for the components: Parsing comments have been used for stuff like type hints / formatting / linting, tho generally not at run time (afaik).

The tooling for finding out where something is called from can be used to give a better understanding of where things go wrong when an exception happens or similar, to add to logs.

I would say that in general you don’t need either functionality except for certain edge-usecases

[–] [email protected] 3 points 4 days ago* (last edited 3 days ago)

Thank you ! 😄

[–] [email protected] 8 points 4 days ago

I'd say nothing that can't be achieved by docstrings.

[–] [email protected] 3 points 3 days ago

We actually use method comments for user documentation as well. Only on specific business methods, but it's nice to have a good comment for the dev and a tooltip for the user at the same time.

[–] [email protected] 1 points 2 days ago

they have to import a separate library to do this, it's not a part of standard python, and this post is basically just misinformation

[–] [email protected] 31 points 4 days ago* (last edited 4 days ago) (1 children)
[–] [email protected] 10 points 4 days ago
[–] [email protected] 3 points 4 days ago* (last edited 4 days ago)

~~It does work~~ I know it at least partially works

class add:
     count = 0

     def __init__(self):
             add.count += 1
             self.value = add.count
     def __str__(self):
             if self.value == 1:
                     return "3"
             elif self.value == 2:
                     return "7"
             else:
                     return "32"

result = add()  # 1 2
print(result)
result = add()  # 3 4
print(result)
result = add()  # 3 4 5 20
print(result)