The Nineteenth Byte

@NumberBasher r/place but made by emanresuA for cgcc

5:46 AM

i'm just looking at some of the standard python library stuff and realizing
there is some truly gratuitous global state shit going on with some of these
like why does the csv module maintain a dialect registry

which reminds me, i still haven't been convinced that there is any legitimate use case for the singleton pattern

@UnrelatedString uni assignments

Singletons are best replaced by static classes where possible.

in flax, 54 secs ago, by PyGamer0

>600 commits !

@UnrelatedString what is a singleton pattern

@lyxal which is the worst part--universities that have bowed down to oop orthodoxy are teaching people bad practices

class Something{
    public static Something INSTANCE;
    public Something(){
        if(INSTANCE != null) throw Exception();
        INSTANCE = this;
    }
}

5:50 AM

public class Singleton {
    private static Singleton instance;
    private int count = 0;

    private Singleton() {
    }

    public static Singleton getInstance() {
        if (instance == null) {
            instance = new Singleton();
        }
        return instance;
    }

    public int getCount() {
        return count++;
    }
}

^

a class that has only one instance and can only have one instance

What I posted is real code from an assignment Daniel gave out

zamn

real code from my project

/shudder

5:51 AM

because it's a requirement to have a singleton

That can very easily be converted to a static class too ;-;

@UnrelatedString how is it useful?

@ATaco no doubt. But it is what it is

public static class Singleton {
    public static int count = 0;
    public static int getCount(){
        return count++;
    }
}

Cleaner, does the same thing. ;-;

the only class i've had in java so far the professor basically threw singletons in completely gratuitously because he knew it was Something You're Supposed to Teach but couldn't contrive something that made sense

5:52 AM

Singletons exist where one cannot avoid writing a singleton due to implementation issues.

actually i forget if it was specifically singletons or if singletons were all he could think of for factories--which can be justified without singetons ofc

Unity often uses Singleton Monobehaviours.

import random
singleton_count = 0
class Singleton:
  def __init__(self):
    if singleton_count > 0: raise Exception("frick you")
    singleton_count += 1
    self.v = random.random()

^ is that a Singleton?

class Singleton:
  __instance = Singleton()
  def __init__(self):
    pass
  def getInstance():
    return __instance

that's more accurate, but not fully the same

mostly because python doesn't private members

@lyxal that is why python should not be used ...

why doesnt python have private members?

5:58 AM

Python can have Private members if you break the language enough.

that's the beauty of it

Oct 21, 2021 at 8:39, by pxeger

TIL Python has a built-in range syntax! https://ato.pxeger.com/run?1=PY5BasMwEEX3PoXIaqaoIlkUioOz7Am8C0Eo9kg12JIZTQIm5CTdZNNeoWfptiep3YYuPh_e58-ft49xktcUb1_fLXlVg9cPFstC-cQqqi5CKCtvvA19Oro-YxkaE0gskyemKBl8n5wYa9uuEWtxvz7s46GSaSSIGlBfVtYuDbsqezccW6dafdZSsouBoIsCZ9Rh7uAVAQvFJCeOqi66YUwsKjQ6T3k7y2QSYdcQ1Lh9qRayXPbsBoKZzG_-xjaNTWop639SbXZrXb-fxD8-f7Kq1FMx8jLdd1lgYwwj_qW3u939Bw

can you even have static class methods in python?

Yes

there's a decorator for it which iirc just ignores the self parameter

6:01 AM

class A:
    @staticmethod
    def static():
        print("hi")

@UnrelatedString it's slightly more complex than that, because when it's called on the class (A.static) there is no self parameter to ignore, but when it's called on an instance (A().static) there still is

oh nice

i did not actually know it let you call it on the class

@pxeger i forgot about that decorator

It actually uses descriptors: docs.python.org/3/howto/…

So I'm trying to create a more accurate python singleton class, but I'm having a little problem

Try it online!

It doesn't like creating a new Singleton inside the class

Number Basher

@PyGamer0 ok

but it has a bug

6:05 AM

canvas

canvas.rto.run

dont ask me

ask emanresu there ^^

@lyxal o__o

@lyxal This is the standard way of doing it: ato.pxeger.com/…

@lyxal wait wont that create recursion?

@pxeger ah I see. That's a much better way than what I was attempting

Try it online!

Python makes me sad.

6:09 AM

hi sad, I'm lyxal

but i only know python properly :(

i should try learning C++

why is your first choice c++ of all things

C++ is cool :P

learn c++ on an as needed basis after learning like three or four related languages

Feb 17 at 19:50, by pxeger

> The official mascot for C++ is an obese, diseased rat named Keith, whose hind leg is missing because it was blown off. The above image is a contemporary version drawn by Richard Stallman.

@UnrelatedString \o/

@UnrelatedString what should i learn then?

you know, i tried making a text editor in Java once..

6:13 AM

depends on how you feel like you need to branch out ig

i got syntax highlighting working

nice

oOoOo

C > C++

Entirely for personal non-objective reasons

well it's true logically too

wait no

no it's not

C == C++

@UnrelatedString then i deleted the code :P

6:15 AM

nice

good call probably

C < ++C

@ATaco true

Except when C is a non-number. Then who knows

C++ is C's younger brother who acts like he wants nothing to do with him but still ultimately shares a lot of hobbies and at the end of the day came from the same place.

6:29 AM

c++ is c's son who's been drifting in and out of rehab for the last 10 years after getting hooked on amphetamines as a rebellious teenager

4

6:41 AM

time to C++

#pragma once

template<typename T>
class Array {
private:
    T *ptr;
    size_t len;
    size_t size;
public:
    Array();
    Array(size_t size);

    ~Array();

    Array operator+(Array other);
    Array operator-(Array other);
    Array operator*(Array other);
    Array operator~(Array other);
};

any c++ users here ?

will ^^ overload ~ so i can do: Array~Array?

i don't think you can have binary ~

been a while though

Honestly missed opportunity.

I use it for Binary XOR, but I also use ^ for Power

yeah

honestly surprised that isn't mainstream lmao

@ATaco wait so can i overload it or not?

like if you're going to have variadic operators for + and - already why not put xor on binary ~ so you can save ^ for exponentiation

6:50 AM

i am making binary ~ concat

Ah, I usually use ..

But i have the freedom to choose in my project

i'd probably go with ++ or maybe something funky like <> or +: if i designed a praclang

, is the best option..

it even makes sense

oh yeah ; is an option

@UnrelatedString but thats the statement separator..

7:00 AM

in general, not c++

Funky2/3 just have you splat onto a new list anyway

oh ok

c = [a..., b...]

considering i'm fairly sure c++ doesn't let you overload the comma operator :P

@ATaco is funky3 a practical language?

@UnrelatedString i think it doesnt

7:00 AM

More-or-less.

It's not esoteric, but it definitely has quirks.

I'm a big fan of the De-Operator.

the default.

@UnrelatedString it does

wait really

wack but also nice

7:17 AM

@thedefault. oh cool

@ATaco de-operatpr?

/deop ATaco

Not sure the equivalent in other languages, but it allows one to get a function from an operator

f=@+; print(f(3,5)) $$ returns "8"

An expression can be provided instead of an operator to instead act as a lambda function. EG. f=@print("Hello, World"); f(); f(); $$ prints "Hello, World!" twice.

The main use is as a function argument for something like sort or reduce.

Aiden Chow

isnt that kinda like lambda in python

@RadvylfPrograms Is this answer valid? You can't write a valid full program in Haskell without using =, because you need it to declare main, but you can write a valid module which compiles fine: Try it online!

You can write interesting functions, too, like (+1).(*3) to perform one step of the Collatz conjecture