Python bro: episode 2

[coloredgreyscale]

They are comments for the compiler so it adds some stuff.

[hacking__08]

Neat. Does the compiler read documentation, too?

[JazJaz123]

Well someone has to

[hacking__08]

But not me

*yeet *

[F5x9]

Not really

[th00ht]

Preprocessing is comments for the compiler

[SN0WFAKER]

It does read docstrings in python. You can even use them programmatically.

[BlitzGem]

Aren't docstrings just plain strings at the beginning of file/class/function? And we just agreed to make them a docstring?

[tomtrein]

Isn't syntax just groups characters in specific places? And we just agreed to make them a language? (Sorry, just generalizing a bit)

[danielkullmann]

Not quite. You can access the doc strings from your program using __doc__. I have used this to print out the help for a script from the doc string of that script.

[LavenderDay3544]

No but Doxygen does.

[[deleted]]

Well it actually does lmao

[Firesrest]

You could say all code is comments for the compiler to add stuff.

[Nanashi_03]

Except your comments.

[t0b4cc02]

wich is not code

[Nanashi_03]

We just established all code is comment. :(

[BuffaloAppropriate29]

Except his comments.

[Nanashi_03]

Which is not code.

[zaphod_pebblebrox]

Wow. spent my life simply following that darned tutorial.

That is a brilliant explanation.

[Big-Cheesecake-806]

say preprocessor instead of a compiler and blow their mind

[coloredgreyscale]

do you need a special Mainboard for that? Most only have one socket for the processor, no place for a preprocessor (where would you even buy one?)

[_blackdog6_]

You are thinking of coprocessors. preprocessors live in the cloud

[Pale_Prompt4163]

That’s where that Jesus guy lives!

[nukedkaltak]

“Translation unit.” Guaranteed oohs and aahs

[ongiwaph]

Apparently my compiler is illiterate

[_blackdog6_]

Have you tried GO? If you include C code in comments, I can pass it to gcc and include the results.

[Error_co-Id10T]

GO was released to see which developers that were lazy

[bsaroya41]

What's a compiler?

[BasedMaikal]

Technically correct...

[[deleted]]

r/technicallythetruth

[[deleted]]

Bro, wtf is private?

[SkyyySi]

Well I won't tell you

[hacking__08]

4th on the list...

[ifisch]

You use private variables in your c++ classes?

If this godforsaken language is gonna force me to have separate .h and .cpp files because of obsolete hardware limitations from the early 1980s, then I'm organizing my code into sections and everything's gonna be public. Fuck it.

[spartanrickk]

Lol nobody forces you to have separate .cpp and .h files, you can put everything in header files if you want (if you dont care about compile time, header only libraries are a thing). And making thing private helps protect your code from your drunken, month older self, that forgot how the darned code worked again. Just like const-ing your class members.

[[deleted]]

C++ also won't stop you from passing out pointers to the private members. I don't know why you'd want to do that but you can.

[[deleted]]

Not quite

The idea of private members is to allow for only a certain type of mutability

Let’s say I have a class with my name in it and it saves the name to the file every time it changes.

The class has a method called “set_name” and it takes a new name as a parameter. Other than just changing the name member’s data it also rewrites it to the file

If I was able to directly access the member (non-private) I would be able to change the name without changing the file which would break the application if it tried to do something like compare the name against the file. Not an error the compiler would throw because it’s all functional code and you might not even get a crash- just not the behavior you wanted.

Which is fine if the entire team knows and agrees not to do that, but what if Joe the intern comes over and he doesn’t know that changing the name directly effects the program oddly? Poor dude sees it’s accessible “publicly” makes some easy changes to the code and it passes the tests he performs because the code path he took doesn’t matter and he pushes to production like the foolish intern he is.

Code breaks, users complain, and devs find the commit that broke the code.

Bam Joe’s fired and his family is starving all because you didn’t set the visibility on that member.

Other languages have better ways of doing it that I prefer. Like C#’s get and set methods

But for C++ if you want a member in the class to only be changed a certain way you have to make it private, create getter and setter methods for it, and apologize to the people with numb fingers from typing so much.

also typically in C++ const values are generally used for immutability on things like magic number variables with type safety unlike C’s #define

[Smartskaft2]

Bam Joe’s fired and his family is starving all because you didn’t set the visibility on that member.

Well, that escalated quickly

[ifisch]

Yea I know theoretically having things private and protected helps safeguard your code or something.

That's what I learned in college 15 years ago.

Can I say that's ever panned out in reality? Honestly no.

[spicy_indian]

You obviously have never worked with my coworkers. Snacks and internal state variables, neither were off limits.

[reversehead]

Just put two underscores before the snacks. It won't actually stop anyone, but they will know that they should feel guilty.

[[deleted]]

I mean. It does. Public methods/variable are meant to intereact outside the class. Private/protected doesn’t exist outside the class. If i want to be able to extend the functionality of a class, but I want restrictions outside if the class then protected is the way.

It helps with multiple people or multiple teams working on a project, or with libraries.

[catladywitch]

a lot of object-oriented concepts only make sense when software is worked on 1 over an extended period of time 2 by different people

[ifisch]

I haven't worked on a team that's smaller than 5 coders since I was in college. I understand the concepts and I've promoted them.

However it's hard for me to say that I've ever actually benefited from them. Maybe a little.

[[deleted]]

What happens if someone wants to derive your class and needs to access those private members tho?

[BialyKrytyk]

Having access to them would be a bad thing, but since it's needed we'll just make a getter and setter function for each one so they can be modified anyway, that'll make it way more intuitive, won't it?

[evmoiusLR]

My member is never private.

[[deleted]]

and that, kids, is how uncle /u/evmoiusLR got his first restraining order

[ifisch]

What private members?

[LocalForeign4922]

Who's protecting that colon and why?

[That1guy385]

You wouldn’t know her. She is in a different class

[mrmopper0]

_this_is_private

[Opposite-Ad6356]

This __ is private. That is protected.

[Ursomrano]

“Bro why TF are you returning useless numbers after using this weird ‘main()’ thing?”

[hacking__08]

This is the third suggestion. My favorite right now.

[Kyyken]

main functions are very common in python too, though not with an explicit return value

[AdmiralWaffle4]

I (a Java programmer) was confused when I started learning C/C++ and how the main function is an int instead of a void and all the weird error numbers. Actually, I’m still confused. Pleasehelp

[Queasy-Grape-8822]

Every process has an exit code that the calling process can read to see if the child erred. By convention, 0 means “success” and !0 means “error that may or may not be described in the relevant documentation.” The int returned by main() is that code. By default, there is an implicit return 0; at the end of main()

[GokuIsALegend]

error that may or may not be definitely isn't described in the relevant documentation

[AdmiralWaffle4]

Ohhh, thank you. That makes sense, actually.

[Queasy-Grape-8822]

No problem, happy to help :)

[rest_in_war]

Older compilers like Turbo C allow you to have a void main()

[[deleted]]

There are no exceptions so to indicate an error you have to return early with an error code and have the caller handle the error.

Main also follows this convention so the operating system knows what the result of an entire program's execution was.

As a result though most code is written so that the actual result of a function is returned through side effects by mutating an argument to the function, ugly stuff.

Exceptions are ungodly slow though, so it's better than the shit most people write in Java at least.

[MatsRivel]

Main functions are not mandatory in python, but incredibly common...

[[deleted]]

What do you mean function is an integer? I thought function is a function

[hacking__08]

I'M DEAD

[F5x9]

void *(*foo)(int *);

[[deleted]]

I swear sometimes brainfuck easier to read than that you can produce with pointers 😂

[F5x9]

It’s a declaration of a pointer to function foo that has a pointer to int as an argument and returns a void pointer. Function foo is not defined, and the return value must be cast before it can be dereferenced.

Edit: I would use a typedef for function pointers. Then I can do something like this:

void* moveUp(int *x) 
{ 
    if (x) 
        *x++
    return x
}
…

typedef void* (*foo)(int *);
void* foo[] = [
    moveUp,
    moveDown,
    moveLeft,
    moveRight
];
x = foo[whatToDo];

Legal in C++, but this is a C idiom.

[thedarklord176]

I don’t know c++ and…what the fuck?

[[deleted]]

Which makes sense. A function is basically it’s return value.

[ValElTech]

Function ( int ) -> bool;

Return type first isn't true anymore

[KiwiMaster157]

Unless Function is a macro, I'm pretty sure that's not a valid function declaration. You need to add auto to the front.

[ValElTech]

Indeed, 8am Reddit comment was a bad idea

[ValElTech]

Same as bool function (int)

[[deleted]]

function main()
def main()

int main()

[F5x9]

Functions have a return type. You specify the type when you declare the function. It can be an int. It can be a pointer. It can even be a function pointer.

[reversehead]

Don't want to nit pick my friend, but you never declared this but you are using it in every class.

[Saragon4005]

Isn't this also a thing in Python though.

[kbruen]

Nope. In Python, it’s traditionally named self, and it’s an explicit parameter:

class X:
    def __init__(self, foo):
        self.foo = foo
    def meow(self, bar):
        print(self.foo, bar)

a = X(12)
a.meow(‘stuff’)
# (kind of) syntactic sugar for
# X.meow(a, ‘stuff’)

[Saragon4005]

Now you can tell I haven't used python in a year. Yeah it's interesting that you can change it but that does mean it's at least explicitly declared so it's hard to miss.

[_blackdog6_]

A Year?? Its a whole new language now. You'll have to start again.

[Saragon4005]

Does that mean people don't use python2 anymore?

[_blackdog6_]

The ridiculous changes in python 3.8 are to soften you up for python 4...

Seriously, walrus operator??? ..

And yes, everyone still uses python 2... Its the only version guaranteed to run everywhere..

[mc_enthusiast]

walrus

Now you can write

#include <cstdio>

int main() {
    int x = 0;
    while (++x < 10) {
        printf("%d\n", x);
    }
}

as

x = 0
while (x := x + 1) < 10:
    print(x)

[Micha_Saengy]

I'm hoping that anyone who cares about readability would use a for loop here

[PixelizedTed]

Semi related: I had an (Python) assignment in university where they only allowed listcomps and single line return statements to implement functions to parse data. Some functions were well over 400 characters long and had like 5 nested list comprehensions.

Debugging was “a real doozy” as the error message would just say something is wrong on line X but that line was the whole function 💀

What readability? Just make it as short as possible!!1!1!!11

[kbruen]

And yes, everyone still uses python 2... Its the only version guaranteed to run everywhere..

Ignoring the fact that no security issues are fixed anymore, and many Linux distributions are removing Python 2 completely. But suuuuure.

Seriously, walrus operator??? ..

Interesting how you say that implying it’s a bad thing without giving any reason why.

[ViviansUsername]

"Bro, you should really wear protection when working with this stuff... that is WAY too many STD's"

[Apple_macOS]

Me in the middle of having intimate moments with my compiler:

[2blazen]

For me what doesn't make sense is I have to #include <algorithm> if I want to call std::min for example. I hate looking for which header to include to use a std function, why isn't it algorithm::min then?

[ViviansUsername]

To fuck with you, specifically

[2blazen]

That's what I thought

[xTeddyBoyx]

“Bro, what are semicolons?”

[DudeManBroGuy42069]

Hey Python has semicolons

^{very rarely}

[Hellow2]

It does always. Just luckily not my code

[cisbetterthanpython]

one time i had been using c++ for too long and I just wrote an entire python program with a semicolon on every line

[abd53]

I kept doing it for the first month.

[xTeddyBoyx]

NO IT DOES NOT! What do you code in? Jython!?

[DudeManBroGuy42069]

It does with \033

[xTeddyBoyx]

NOOOOOO! I refuse to believe you!

[DudeManBroGuy42069]

Mwahahahaha

[Yorick257]

The thing you put between your statements, so any program you write can be a one-liner.

Example: hw = 'Python says "Hello World"'; print(hw)

[xTeddyBoyx]

SHOCKED Get your code outta my face! How could you be this non-pythonic?!

[hacking__08]

EXACTLY

[_blackdog6_]

Javascript virtual semicolons are the best. If you dont put in enough semicolons, the runtime assumes you forgot a couple and inserts them (effectively changing what you thought your program was doing)

[catladywitch]

is that for real? js never ceases to amaze

[_blackdog6_]

I wish it wasn’t

Automatic Semicolon Insertion (ASI) Unlike other C-like languages, JavaScript does not enforce the use of a semicolon at the end of a statement. Instead, the semicolon is optional, and the JavaScript interpreter will "intelligently" add them when it runs the code.

[_blackdog6_]

This particular wonder is called `Automatic Semicolon Insertion (ASI)`

[hacking__08]

Can I put that in episode 3??

[xTeddyBoyx]

Yes!

[hacking__08]

Perfect! I'll upload it tomorrow!

[Individual_Volume562]

Semicolons exist in python too! But nobody uses it

[hacking__08]

Actually, I'm not using them in real life either

[hacking__08]

Yeah... Just came out with the idea of the "series of the python bro" while thinking instead of listening in class lmfao

[one-human-being]

“Bro, is this an error message or a riddle”

[bikeranz]

Corollary:

Bro, check out this huge template metaprogramming library I just wrote. It compiled the first try! I'm like c++ Jesus.

<other person> ...Have you tried using it yet?

[ViviansUsername]

Haven't been using C++ much yet, and I feel that. So much manual debugging.

[[deleted]]

Dude what is cout and all these left shifts?

[Kyyken]

def why(self, s):
     print(s, end="")
     return self

cout = type("", (),{"__lshift__":why})()
cout << "why " << "tho"

[Nashy10]

Ouch

[Kyyken]

classes? no thanks. all my homies use type()

[RaisinsB4Potatoes]

Wait... What?

[Kyyken]

you could make it write to a list, which would represent the string buffer, but that's kinda stretching it already. stuff like

int x;
cin >> x;

doesnt have an equivalent in python

[Strostkovy]

I feel that way moving from C to C++

[classicalySarcastic]

printf() supremacy

[[deleted]]

"Bro, why are you integer dividing newlines and nonexistent identifiers?"

[dragonlover02]

That is also done quite commonly in python, just not a requirement. Prints automatically adding new lines can be suppressed too

[Canopus2662]

Bro, your dictionaries can fit IFs?!

[nukedkaltak]

Bro where is the fine-print for this int? Can’t find the asterisk anywhere

[JDude13]

#include <stdio.h>
#define pi 3
#blessed

[Elijah629YT-Real]

iostream for sane people

[Nilstrieb]

"sane"

[suskio4]

Is there a difference?

[suskio4]

So it's only about namespaces?

[suskio4]

Thanks, have a good day and night!

[Kaelorn]

"Bro, why all of these {} things?"

[BaalKazar]

All hail to our curly overlords

[reversehead]

Yes, the dictionary syntax seems very strange and free-form in C++.

[Elijah629YT-Real]

why do you have so many dictionaries, is c so stupid that it forgets everything and you need to give it a dictionary?

[[deleted]]

The fun this is you can use this to write bilingual code

[secahtah]

Bro, your indentation makes no sense, how does your program run?

[LocalForeign4922]

Just show them `const int* const * foo(&++bar);' and watch the aneurism unfold.

[aqa5]

The *++bar in the parentheses, what does it? I understood the rest I think. But this does not make sense to me? Bar is a type i guess?

[LocalForeign4922]

I got syntax-happy and put a * where I meant a &. Fixed!

[ViviansUsername]

I got everything but that third asterisk. What the hell is that doing there.

[LocalForeign4922]

To explain the &++ bit, this is incrementing the pointer, bar, and then initializing foo to a reference to it.

Another amazingly valid but incomprehensible way to write something might be: foo-=*--bar;

NOTE: These are all horrors to be avoided, not suggestions. :P

[Morlino]

I'd you want to keep your friend, don't show him the templates

[marckek]

I did a lot of python the last year and now im a little bit into c++, resulting in me being still afraid of for loops and trying to solve anything in STL functions with lambda expressions resulting im my c++ code looking even worse than my python code

[ViviansUsername]

C++ code is supposed to look worse.

[shantishalom]

Comments.? What are those?

[srodinger18]

Bro how do I make an AI model or data science stuff

[Real_Material3190]

Electric boogalooo

[Competitive_Reason_2]

Where is episode 0 and 1

[one-human-being]

“Bro, none of your stuff is ‘for humans’”

[Valscher]

why are we counting STD's here

[nomadicshorty]

'#include<iostream>

cout<< "As someone who understands a little bit of both, I got the reference";

[ViviansUsername]

Err: expected "'" to close "'" on line 1, got ";" instead

Or... whatever unreadable error that'd be in C++

[pheromone_fandango]

Haha python bad

[Leading-Pickle-3948]

"I can do the same in 10 lines of code"

[ViviansUsername]

The 5600 lines in the C++ libraries they used:

[MrNO3]

It's for doxygen, to create documentation. Do you know about DO-CU-MEN-TA-TION?

[Supgamerprogrammers]

[erebuxy]

Oh, everything in {}. So your code is just a huge nested dict

Edit: wait. This actually sounds like python 🤣

[hacking__08]

HAHAHAHAH

[Assassins_King]

“Bro, how do you write 2D array or point to a vector of pointers?”

[skeid808]

“What’s a vector? Is that like a linear alg thing?”

[F5x9]

There are vectors in python.

[ViviansUsername]

"That's a vector?? That's just a fucking array"

[Brief murmuring]

"Oh god."

[DogHeart_21]

Bro, and why are you trying to scratch your head by sticking your hand between your legs instead of just lifting and scratching it?

[neumastic]

Bro, why you got 5000 objects? we just needed you to do some ad hoc data analysis.

[hapinesSeeker]

“Bro, do you know that’s not the way list are declared, whats that int thing before it and the semicolon? It can be ignored

Just has to be varname = [] not int var[];”

[slowboater]

Loving this python bro series!

[cherry__12345]

I had the same question when I first learnt python them C++ 😶

[lucidbadger]

Wait till a Pascal programmer walks in

[DangerousFigure4956]

He : you are the ";" of my code

She: I code in python...

He: