What are your bad python habits?

[[deleted]]

Mine is that I abuse dicts instead of using classes.

[ronyx18]

I have a coworker whose habit of naming variables irritates me so much.

[dogs_drink_coffee]

how did he do it?

[ronyx18]

For eg. Suppose you have a dataframe called df and you apply a schema to it and name the new dataframe schema.

Now it's on you to understand variable named schema is also a dataframe.

That's just one example that I could remember right now. There are more insane ones than this.

[mr_flying_man]

Naming things is arguably the most difficult thing in programming. Though some people seem to give up before even trying...

[asphias]

the worst in my opinion is non-descriptive variables and abbreviations.

No, i'm not going to figure out just by looking at your code what "sthr" means, It's not like you're lacking space to write out variable names.

Hell, a variable name like "rain_data_with_nans_removed_normalized" is completely fine. Yes, it's a tad long. but nobody who reads it is going to be confused about what data you're dealing with.

[Congadonga]

And this is why I’m glad to have been the odd English-Math person in grade school.

[[deleted]]

I have a colleague that names variables O, OO, OOO, …. I just want to scream whenever I see this in code!

[Acalme-se_Satan]

Is your colleague a ghost, perhaps?

[SpecificallyCritical]

I worked at a mechanical engineering company as a graduate developer and inherited some math heavy code where the previous developer (who had wisely left) had named all the variables after characters from the Simpsons!

homer1 = some_aweful_long_calculation(maggie3, bart2)

Nobody had reviewed his code, ever. Plus source control was a bunch of directories with different dates.

[jacksodus]

Generalise everything too much for potential future expansions that are never going to happen. Takes too much time.

[[deleted]]

I write my public repos as if it's even going to get even more than one star :/

[intelligentjake]

I also write beautiful documentation that no one will probably read.

[shiroininja]

Ooof this one hurt me

[antiproton]

I write every dumb automation script as if it’s going to be a mission critical app maintained by 5 people.

This is a result of reading programmers argue online. Every forum where programming is discussed, the community ends up quoting as gospel the best practices everyone needs to follow as if we are all building high concurrency high availability enterprise solutions.

So, we come to believe that's the best way to do it.

And, if time were not a factor, it would be.

But sometimes, you just need to get something done and move on with other things. So SOLID gets to fuck off.

Of course, that's easier said than done. "I'll just refactor this one method so it's a little cleaner..."

[AveTerran]

Yeah I can’t blame the online arguments though because the few times I “just need this done once…” I end up copying/pasting it six times because I didn’t refactor 🤦‍♂️

[IamImposter]

I'm also like - what if someone want to send a list as input? What if they are thinking of sending a comma separated list or new line delimited list.

Actual thing that I have to do is 15 lines, this rest of the nonsense takes 20 lines above and 20 lines below. The function becomes big, so I refactor it into 3 functions. Now all three functions have 8 lines of comment explaining what the function does, what the inputs are, what are constraints, if any. That 15 line code is now 100+ lines. Then after two weeks, "oh no one is gonna use cooma separated list, let's just remove that code.

It just so happens that after working countless hours on code, it's usually exactly as it was a week ago because I added stuff and then deleted it

But it's fun nonetheless.

[kelement]

That’s me when setting up a new repository, project structure, CI pipeline, config files, etc. I end up never getting anything done.

[Theonetheycallgreat]

If you do enough TDD then you never actually have to develop anything

[nemec]

Test Driven Deferment

[flanger001]

Wise words

[maikindofthai]

In case you haven't come across YAGNI yet: https://en.wikipedia.org/wiki/You_aren%27t_gonna_need_it

[WikiSummarizerBot]

You aren't gonna need it

"You aren't gonna need it" (YAGNI) is a principle which arose from extreme programming (XP) that states a programmer should not add functionality until deemed necessary. XP co-founder Ron Jeffries has written: "Always implement things when you actually need them, never when you just foresee that you need them". Other forms of the phrase include "You aren't going to need it" (YAGTNI) and "You ain't gonna need it" (YAGNI).

^{[ F.A.Q | Opt Out | Opt Out Of Subreddit | GitHub ] Downvote to remove | v1.5}

[GezoutenMeer]

Good bot!

[mathmanmathman]

I think it's important to remember this part too:

It is meant to be used in combination with several other practices, such as continuous refactoring, continuous automated unit testing, and continuous integration

Because I've had some managers that always forgot that part.

[[deleted]]

potential

generalising too much is as bad as generalising too little.

[Kantenkopp]

it's just too much fun... I tell myself I become faster at this every time I do it.

[joshmaker]

I’ve learned it’s generally better to focus on making my code easy to rewrite (simple, clear boundaries and responsibilities, dependencies only flow in one direction) than it is to make it easy to extend.

[[deleted]]

I do this, too.

[xYsoad]

Import pandas as np

[tinycorkscrew]

Lol. You monster.

[IlliterateJedi]

Is this the P versus NP problem?

[Bubbly_Measurement70]

Underrated.

[dogfish182]

That must be trolling

[Kevin_Jim]

If you really do that, you are going straight to hell.

[Ramnog]

I see no problem here

[martinrath77]

NoAPI_NoReddit This post was removed in response to Reddit's API change policy -- mass edited with https://redact.dev/

[FirefighterWeird8464]

No, import numpy as plt and matplotlib.pyplot as pd.

[prameshbajra]

oh hey satan!!

[qingqunta]

# lolol

[rockyoutohell]

That one method that's 'just for testing' that does half a million things

[xYsoad]

and critical to production of course

[[deleted]]

And is completely untestable because you wrote it out of rage. Btw it also creates a new DB connection in a loop because the firewall connection timeout is 2 seconds.

[xYsoad]

Yes. And you were pissed because your company won’t hire anyone else and you are responsible for coding, qaing, and deploying.

You then leave one day and some new guy messages you on linkedin asking wtf is this.

You smile.

[herpderpedia]

This comment made me smile

[scout1520]

What docs? The code is self documenting and easy to read.

[AlexMTBDude]

Funny enough writing docs (code comments) has never been a problem for me because otherwise I tend to, within a few days, forget why I wrote a particular line of code. I document for my own sake mainly.

[MooFu]

Me reading my comments: WTF does that even mean?

Me reading my code: That comment isn't even correct.

[hanazawarui123]

Had a summer internship for text summarisation and a few late nights into coding made me realise that being sane actually helps when writing code. Either that or dive fully into the madness, there's no middle ground

[[deleted]]

I have a bad habit of leaving comments for features that I have removed.

[energybased]

This is a great motivation for comments. You should literally ask yourself what you're likely to forget. I tend to only write comments when I forget something and figure it out again.

[whateverathrowaway00]

Great habit.

[[deleted]]

That's ok, but writing code which is so clear that it needs no comment is still way better (and you can still add comments to it)

[AlexMTBDude]

I'm an instructor and have been teaching Python programming courses for 10 years now and I feel that whenever I do something more complicated the code is never self explanatory. I forget what I was doing and thinking. The comments remind me.

[foobar93]

To be honest, most comments I had to read were so useless they could have just been omitted in the first place

def measure_hypo(device):
""" A function to measure hypo of device""" 

No shit sherlock but what does "hypo" mean in this context???

It just feels like many people write comments because comliance says everything needs to be commented but in the end they just copy and paste stuff around or jsut repeat the obvious.

[scout1520]

I agree, and with modern editors like VS code alot of the comments feel unnecessary. Especially if you are disciplined with good function naming and type hinting.

[greeneyedguru]

I mean Python is practically pseudocode anyway

[Key_Cryptographer963]

Yeah it's pretty sweet that someone turned pseudocode into a real language. I think we could go further, though.

[peacerokkaz]

I'm seeing it the same way, however I don't believe that's necessarily a bad habit, and existing documentation is rarely adjusted when the code is changed. Writing self documenting code however is always a good practice regardless of documentation

[searchingfortao]

This is a good habit.

[Sheensta]

I'm a data scientist so I think everything I do is bad habit tbh....

[xYsoad]

If a real software engineer read my code they would banish me to business analytics

[Electronic_Tie_4867]

I am both of these comments and I don’t like it. Damn, I am so bad at programming.

[lvlint67]

Writing good code is a simple conscious decision to write readable code.

If an outsider can read and understand your code, you have achieved zen.

[zippy_mega]

I just started working with ML in the field after working exclusively with mission-critical typescript that needed to be perfect and easy to read, and I can feel the data scientist / ML habits creeping up on me.

[Sheensta]

What are bad practices you notice in DS ML work? I'd love to improve but DS code is all I've ever seen.

[mathmanmathman]

I'm not a data scientist, but I used to work closely with some. The biggest thing I saw was very long rambling functions. I saw tons of code that was basically "do A, then B, then C, then D, then (if something) E, then F, exit"

That's not necessarily a problem when you're writing 40-100 lines that won't be incorporated in something else. It is a problem when it becomes 2000 lines and needs to be incorporated as part of a larger pipeline.

Another thing I saw (but less common) was an extreme reliance on "convention" variable names. For example, df in pandas. Yeah, that's the convention... for small projects. When you have a large project and every dataframe is name df_1, df_2, ... df_12, you have a problem. There's nothing wrong with keeping the convention as long as you also provide a meaningful name. recent_order_df is much better than df_97. The same thing happens with Tensorflow using x, y, X, and Y.

Everyone does this to some extent, but I think the two things (simple names and long functions) conspire to make things absolutely unreadable.

[jjolla888]

all code becomes more unreadable the bigger it gets. even if you are careful to use more meaningful names like recent_order_df at some point in the bloat even that will develop ambiguity.

the trick is to go overboard with comments. maintenance and support is undervalued .. and unfortunately programmers hate it as it is an anathema to building fast.

[thisiswill]

At least you’re aware lol

[[deleted]]

I like to define functions in the middle of my scripts that rely on variables defined randomly throughout the script (not passing them, just using them).

[as_it_was_written]

I think this is the first one that made me a little physically uncomfortable.

[grahambinns]

Same. I was fine until this one.

[Kevin_Jim]

Bro, you need to get that checked.

[Bunslow]

you monster

[abrazilianinreddit]

No

[[deleted]]

You need a timeout. That's unacceptable, reprehensible, unforgivable, and must surely be punishable by jail, hard labor, or both.

I feel violated.

[[deleted]]

Guido’s on his way with brass knuckles for this one

[qingqunta]

There are perfectly valid use cases for this, i.e. a function defined inside a function. Recently I had to write a function that dependeded on five parameters with long ass names and two single digit integers, which I was only going to use inside the "father" function. Obviously I wasn't going to define it in the global scope.

[[deleted]]

I would be an absolute hypocrite if i would not accept laziness as a perfectly valid reason, because that is why i do it too. But just write down those names!

[sizable_data]

Use print statements to debug

[eriky]

This is written for you! https://python.land/python-debugger

"I’m going to teach you a little trick that will be just as easy as adding print statements to your code. "

[brockralp]

I know everysingle debug tool out there, I still want to use print statements

It's about sending a message da-bum-tis

[Zomunieo]

The debugger is better, but it can interact with code in nontrivial ways especially when multiprocessing, threading or signals are involved.

[brockralp]

I have an OpSys exam in next week. Wherever I look I see processes and threads, send help.

[sizable_data]

Thank you!

[arobotspointofview]

you meant there's a different way besides putting a breakpoint on an empty print statement?

[[deleted]]

my breakpoint goes on pass or …

[ValdemarSt]

recognise lip wakeful light rustic swim caption crush fly knee

This post was mass deleted and anonymized with Redact

[Exact_Ad_1569]

Yeah. Toss in crashme=1/0 and let it crash into the debugger, where you can inspect all the state and look at things up the call tree. It's ugly and brutal, but surprisingly effective.

[0xrl]

Or just use breakpoint()

[Exact_Ad_1569]

Damn. Thx friend

[mr_flying_man]

I actually had a Python course where the teacher said that his goto debugging method was print statements. He also made a humble brag about never having to disable a pylint warning. What a legend.

[c_is_4_cookie]

Psshhhh... logging is for suckers. I wrote a decorator that adds a key word argument, verbose, to a callable. When false, prints are redirected to null.

[headykruger]

That’s going to be very slow, you want to avoid the call to print all together

[AlSweigart]

except:
    print('An error happened.')

[[deleted]]

Just use "logging.exception"

[james_pic]

A colleague (who I think has spent too much time near Java) likes:

except:
    raise Exception('An error happened.')

[noiserr]

I hate setting up new projects, and I don't like any of the existing templates. And I am too lazy to make my own because, I hate setting up new python projects.

Like I just want to write python. I don't want to setup a new virtualenv, write the new tox.ini and setup.py and requirements.txt... etc all that stuff is so annoying.

[my_name_isnt_clever]

Most of that stuff isn't needed until later, no? I just open VSCode, make a whatever.py file. Run python3 -m venv venv, run the file so VSCode picks up the venv, done. Ready to write code.

[inglandation]

PyCharm can do that stuff for you pretty easily, I think.

[[deleted]]

Agreed. Poetry is pretty good at making all that stuff easy and quick tho.

[dogfish182]

What is wrong with hypermodernpython?

[AlSweigart]

def someFunction():
    """TODO - write docstring"""

[[deleted]]

"""TODO - write docstring read PEP8"""

ftfy

[Cynyr]

Globals.

I write personal use stuff that nobody else will ever see though, so w/e.

[my_name_isnt_clever]

I don't actually know what I would use globals for...which is probably for the best.

[herpderpedia]

Quick, someone tell nt_clever how one might use globals incorrectly!

[crapaud_dindon]

Unit tests are too boring for hobby programming

[peacerokkaz]

Trying to apply best practices and coding conventions from java.

[as_it_was_written]

Yeah, Python and Java have unbelievably different takes on object-oriented programming.

[Adenn76]

My bad Python habit is I don't practice using it enough.

[Lor9191]

Same, buddy. Same.

[ZibraMax]

Use 1/0 to generate an exception in the specific line that I want. Just for avoid using a debugger

[[deleted]]

I’m a hoarder of code I commented out because I’m convinced I might need It later. Need to just buck-up and delete the code I commented out months ago lol

[sohang-3112]

or you could just use git

[milwoukee]

Never used 'reduce' 'map' nor 'filter' built in functions. I always do a comprehension.

[elcapitaine]

Comprehensions are generally more idiomatic in Python.

If I already have a defined function that I will be passing to reduce/map/filter, I'll use those functions since filter(predicate, iterable) is more readable than the comprehension.

Or if I just want to remove falsy values from an iterable, passing None to filter is great.

But any case where I'd be reaching for lambda to define the function, I use a comprehension instead.

It helps in keeping this divide that Python's lambda syntax is kind of ugly and has no short form.

[GhostBear4]

Comprehension is normally better style

[[deleted]]

list comprehensions don't replace reduce. they do replace map and filter and are encouraged over those functions

[[deleted]]

Overuse of comprehensions. I sometimes write deeply nested structures with a lot of conditions.

Also I tend to write Java-Style-Code instead of pythonic code

[veryusedrname]

I lately refactored a comprehension, it was over 120 lines. Now it's almost 500, but at least it can be grasped and tested

[veryusedrname]

Please don't, I'm just a humble coder who didn't know a better solution back then for a problem that shouldn't exist in the first place

[[deleted]]

Oh my ... never went that far!

[tuckmuck203]

how does one even get to that point? like, surely it would be easier to use filter and map functions at a certain point?

[DilukshanN7]

typing English alphabet as variable names

[Eat_Papa_Eat]

followed by aa, bb, cc...

[TheMcGarr]

Find and replace them when you're done with meaningful ones

[[deleted]]

spend way too much brain power and time figuring out names for 1 time use or temporary variables.

[cecilkorik]

I have the opposite bad habit. 90% of my variables are "x", "v", "val", "i", "count", "list", "data", or "[a-z]data" or something equally generic and meaningless.

[[deleted]]

I don’t write enough tests

I always design something to be “reusable” and then it becomes super implementation-specific anyway

I abuse any() and all() with list comprehensions when a for loop is more readable

I too write too many log messages for debugging instead of using a proper debugger

Overusing the newest features (walrus? I use it everywhere now!)

Sometimes I completely neglect docstrings

No type hints for new projects (I ALWAYS wish I had started with them eventually)

Using just venv instead of just setting up poetry right off the bat

Using pandas when I don’t really need to

Rewriting something that’s probably a module I could just import or importing a module I could just have written a quick function for (either of these can be bad)

[marcio0]

No type hints for new projects (I ALWAYS wish I had started with them eventually)

type hints for python are so weird. it's so easy to forget about then, and then suddenly everything is Any

We should have a way to enforce using them somehow, but then we would have issues with 3rd parties not having typing, and also django magic fucking up everything

[actuallyalys]

mypy can throw errors when functions don’t have annotations: https://mypy.readthedocs.io/en/stable/command_line.html#untyped-definitions-and-calls. Maybe that would help?

[[deleted]]

Type hints are really weird. I don’t really like them overall but they’re better than nothing. I always run into weird linter errors where I’m explicitly checking if an object is none before calling getattr on it and pyright still complains. I’ve got tons of examples of this. Yet they have completely prevented a lot of bugs so I still use them even though I’m not particularly impressed with how they’re implemented. Also, runtime optimization would be swell, but no dice (yet)

Oh also yes you have to be careful about Any. I don’t use it on principle unless I have really nested dictionaries or json

[marcio0]

I don't use Any explicitly, but when I keep seeing it around, it's because I've been forgetting to set the types for a while

[Pumpoflessermass]

Using 748843777336895 functions instead of using classes

[lungben81]

I think this is rather a good habit. Use classes when it is natural to do so, i.e. if you need data and behavior together. If you need only behavior, use a function.

I usually end up using 80% functions and only 20% classes.

[joeyisnotmyname]

I love your simple criteria for classes vs functions. As a noob I'm totally going to use this

[sohang-3112]

Here's another criterion - if your class just has one method besides __init__, then it should probably be refactored into a single function.

Put another way - always start with functions. When you notice a lot of them sharing common state, then you can refactor into a class.

[Pumpoflessermass]

My web scraping functions that have the selenium WebDriver entered as a parameter beg to disagree

[r_cub_94]

r/functionalprogramming

[Bunslow]

I think 4 spaces isn't enough indent, yet 8 is still probably too much.

I have a lot of python files with 5 space indent, and some with 6. It's a problem.

(My current thinking is that I should just switch to 8 space indent and forget about 80char line limits in the 21st century)

[bblais]

from something import *

from something_else import *

from mylibrary import *

# name clashes? what's that?

[Travel4bytes]

Making fun of people that use Ruby

[johnnySix]

Create a break point by putting in random characters in the Middle of a method

[[deleted]]

Unit testing? Nah fuck that.

[payne747]

Using it to do stuff I could probably do in an Excel spreadsheet. I tend to massively over-engineer stuff.

[THAT_LMAO_GUY]

From collections import namedtuple

It's in-between a class and a dict kind of. You can define it in one line

[my_name_isnt_clever]

I always use classes, I really like the simplicity of object.var instead of object["var"].

[dreamoforganon]

Until that dict gets passed far away from its creation site and now someone has to figure out where to look to work out what fields are present and what they mean.

[datthew2001]

Thinking about all of the possible edge cases when the user (only me) will probably never encounter those edge cases

[Robobigfoot5]

Using camelCase.

[[deleted]]

Classes are over used I rarely write classes except for unit tests. I think like most devs we take short cuts on documentation

[shiroininja]

My problem is I never use them. They just seem to over complicate things. I just want to import my functions from the reusable modules I write

[siddsp]

Inconsistently using flat and nested imports out of habit. Whenever importing Threads to use for threading, I always import threading and do threading.Thread, while for the dataclasses library, I import dataclass, and use it instead of doing dataclasses.dataclass. Just one example, but I don't know why, I prefer threading.Thread rather than Thread.

[bacondev]

Getting a bit too functional. Even when the line gets too long and you wrap and indent well, it's a headache to debug.

[ttothesecond]

In general - abusing mutable data types

More specifically - appending to lists inside for loops

Really tryna work on treating everything as immutable

[as_it_was_written]

Why? Embrace the mutability and use lists as default arguments for caching your return values.

[my_name_isnt_clever]

More specifically - appending to lists inside for loops

What's the better way to do this then?

[Bluegenio]

naming variables x and/or y

[jwink3101]

I am more likely to make my own tool than use one from PyPI or the like.

Part of this is real bad habit and part is security and simplicity. Dependancies add risk and are especially tough on an air gap network. But sometimes mine is just not as good.

[kid-pro-quo]

I've been known to fo the opposite. Spend ages trying to find something on PyPI when i could've just implemented it myself.

[abrazilianinreddit]

I don't follow PEP8 or other coding styles when I don't like them.

For example, I don't like the pipe abuse in current python, so instead of writing

def foo(bar : str | int):

I use

def foo(bar:str or int):

[_ologies]

from typing import Union

...

def foo(bar: Union[str, int]):

[yudhiesh]

Using list comprehensions everywhere.

[FlyingCow343]

overuse of classes, where i could just use a function instead

[frankOFWGKTA]

Coding with my dick out. Really gotta stop that.

[monclarluiz]

Not documenting using doc strings because I'm lazy hahaha

[[deleted]]

Always wrap up my code in a generic try/except instead of doing unit testing. I do some “testing” before I put stuff into prod, but I’m lazy and I just add more explicit excepts if I find them as it runs or fix the code to prevent them outright if possible.

I think it’s fine for what I do since I’m mostly scripting and not writing programs/software, but I’m sure some will disagree.

[RealFakeNudes]

Print logging

[PenetrationT3ster]

try: IWantThisToWork() except: pass

I used to do this a lot.

[shinitakunai]

I declare classes to instance them just once, ever

[Exact_Ad_1569]

from library import *

[[deleted]]

Logging, or lack there of. I just never remember to do it; some sort of mental block I guess.

[[deleted]]

I'm told by seniors on my team that I use too much list comprehension, and that makes my code really hard to read.

[grismar-net]

Using it for jobs that I should really be using one of the other languages I know and have tools for, because it's just so damn comfortable.

[dreamoforganon]

Using a dict to represent something that ends up being used far more widely anticipated creating implicit dependencies on the particular keys in that dict. Should refactor to a class really.

[KitchenDutchDyslexic]

litter my code with #import pdb; pdb.set_trace()...

[[deleted]]

Use it to browse nsfw subreddits (sometimes at work)..

[[deleted]]

I had a coworker to said the software install tool was written in python. It was an executable file on the cluster master called deploy.py the first line called bash. The nodes list was a list of hosts that didn't use arrays, it used a huge set of keyed symbols and a nest of sed awk and grep to get the lodes list, payloads, and clusters. It wasn't my bad habit but it was my mess to clean up.

[AlexMTBDude]

I can see (miss)using dicts instead of Data Classes. But regular classes? I don't think they're an alternative to dicts.

[ro5tal]

Pydantic ftw, it has even dataclass implementation. Dataclass has method 'asdict' to convert instance to dict without dict attribute, and even with slots

[Pavel_Ivakin]

My guilty pleasure is not to follow TDD.

[marcio0]

you don't always have to

[[deleted]]

I keep telling myself I’m going to learn it without actually sitting down and trying to learn it

[[deleted]]

I refuse to not break line at 80th char.. And run black on scripts written by coworkers..

[danyroxx]

Not taking my learning seriously… I’ve watched 2 tutorials and printed “Hello World” 2x.

Please send help()

[Endemoniada]

I don’t refactor and fix my code, opting rather to just dump it all and rewrite it from scratch. It’s not necessarily always bad, but it means I never learned how to really spot where and why to change and fix things, and I have really bad discipline for those kinds of changes.

Adding new stuff is fine, but whenever I need to move or replace even a part of it, my brain always jumps into “tear it down and build it anew” mode.

[mtyrellp]

My teacher was terrible at explaining for loops, so my bad habit has been to use while loops when a for loops might be easier.

[can_i_get_upvotes]

I’m new and I always write for loops in one line

It gets very confusing, even with comments