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.
Why would python even expose the current line number? What’s it useful for?
On a serious note:
This feature is actually very useful. Libraries can use it create neat error messages. It is also needed when logging information to a file.
You should however never ever parse the source code and react to it differently.
You underestimate the power of us, print debuggers.
Why wouldn’t it? Lots of languages do. In C++ you have
__LINE__
.Because it doesn’t seem like a useful feature. The only occasion I imagine this could be helpful is with logging to the console to track when the function breaks, but even then - still trivial to replace.
A lot of languages expose it for debugging purposes. It’s available in pretty much every mainstream language (though in some it’s a little more involved, like Java’s
new Exception().getStackTrace()[0].getLineNumber()
).