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[Orange Wizard]

Lisp is a thing because people haven't heard of Python.

[Squeegy]

One thing Java does that I've never seen any other language do as well is class inheritance. And to some extent, function redundancy. Otherwise it's pretty shitty.

[Putnam]

Python's class inheritance:

Code: [Select]

class Fizz:
    def __init__():
        self.fizz='fizz'
    def gimme_fizz(amount):
        if amount%3==0:
            print('fizz')
        else:
            print(amount)

class Buzz(Fizz):
    def __init__():
        self.buzz = 'buzz'
        Fizz.__init__()
    def gimme_buzz(amount):
        if amount%5==0:
            print('buzz')

a_buzzy_thing=Buzz()

a_buzzy_thing.gimme_fizz(3)

> 'fizz'

a_buzzy_thing.gimme_buzz(4)

> '4'

certainly not bad, though I didn't test this code.

[Squeegy]

Yeah, ok, now try putting those classes in separate files and making a buzzy thing in a third file.

e: Oh yeah and all three are in different folders.

[Orange Wizard]

In your parent directory:

Code: [Select]

from folder1.fileA import Fizz
from folder2.fileB import Buzz
from folder3.fileC import Thosethingsthatyouwantedtodo

[Squeegy]

Wrong, actually:

Code: (Fizz.py) [Select]

class Fizz:
    def __init__():
        self.fizz='fizz'
    def gimme_fizz(amount):
        if amount%3==0:
            print('fizz')
        else:
            print(amount)


Code: (Buzz.py) [Select]

from folder1.Fizz import Fizz
class Buzz(Fizz):
    def __init__():
        self.buzz = 'buzz'
        super(Fizz,self).__init__()
    def gimme_fizz(amount):
        return super(Fizz,self).gimme_fizz(amount)
    def gimme_buzz(amount):
        if amount%5==0:
            print('buzz')


Code: (main.py) [Select]

from folder2.buzz import Buzz
a_buzzy_thing=Buzz()

a_buzzy_thing.gimme_fizz(3)

> 'fizz'

a_buzzy_thing.gimme_buzz(4)

> '4'
Also every folder has to have an __init__.py.

E for effort, though.

e: Looks like you don't have to explicitly define an inherited class's function and call it as a super anymore. Not sure when that got changed, you definitely had to when I first used inherited classes, or it would crash.

[Orange Wizard]

Spoiler (click to show/hide)

Both would work. In my example, when "class Buzz(Fizz)" is called, the class Fizz already exists as a global object. When all of the "gimme" functions are called (as part of the import statement), Fizz as well has already been imported.

Also every folder has to have an __init__.py.

And I'm 90% sure this isn't the case, but I may be mistaken.

Edit: Wait, never mind. Just tested this. I'm talking out of my arse. Ignore me.

[Squeegy]

Yes, but your example involves importing every single class held in a separate file into your main file, which is frankly just bad technique. The inheritance should be self-contained. You don't need Fizz for your main program, you only need Buzz, so you should only have to import Buzz.

Also, I'm 100% sure it's the case (I should know, I'm actively using Python). Otherwise you get this error:

ImportError: No module named Buzz

__init__.py is what lets the program know that the folder it's in is part of the program's filesystem. It will ignore any folder that doesn't have that in it.

On the plus side, you can put variables and stuff in __init__.py and call it directly, which I use for certain purposes. Since you apparently don't need to redeclare inherited functions anymore, Java loses its place as 'best at inherited classes' and is only best at redundant functions (i.e. a function with the same name that does the same thing but has multiple possible inputs).

[Orange Wizard]

Yeah, I see. I'm also actively using Python, but I have little experience with all this subdirectory malarkey.
I can say that Python can do multiple possible inputs for a function, but it's probably highly impractical. I have no idea how Java does it.

[Squeegy]

Python does it like this:

def handleMsg(self,type,format=[''],extraTags=[],s_vars={}):
handleMsg("test")
handleMsg("test",[])
handleMsg("test",extraTags=["",""])
handleMsg("test",[''],[],{})

But it's very rigid and inflexible and only those variables can be called.

Java does it like this:

public final static double div(final double a, final double b)
{
   return a/b;
}
public final static double div(final double a, final int b)
{
   return a/((double)b);
}
public final static double div(final int a, final double b)
{
   return ((double)a)/b;
}
public final static double div(final double a, final long b)
{
   return a/((double)b);
}
public final static double div(final long a, final double b)
{
   return ((double)a)/b;
}
div(1,2.0)
div(2.0,1)
div(2.0,2.0)
div(1,1)

All of those are valid under the exact same method. It simply calls the one that uses the right variable types. You can also use it to make arguments optional, like Python does above. Sure, differentiating between doubles and ints isn't necessary in Python, but that's not the only case when having a function that does different things depending on what variables are put in might be useful; I actually think Python loses some functionality in exchange for flexibility by not assigning variables an inherent type.

[Mephisto]

But it's very rigid and inflexible and only those variables can be called.

Method args in Python are about as non-rigid as they can get. If you include args and kwargs, you can pass random parameters to your heart's content.

[Squeegy]

Yes, but they're random and therefore unpredictable. Frankly, **kwargs is pretty useless unless you know what you're passing to it ahead of time, and then you need to determine which set of arguments you're using... just having multiple functions is much more elegant. **args is arguably more useful but still hardly ever used; even the Python docs say that it's rarely implemented.

[alexandertnt]

Why is lisp even a thing?

Because its fun to scare OO programmers with

[Orange Wizard]

I'm pretty sure you can get around the inflexible method arguments if you nest a few dozen "if" statements.

[Erils]

I'm just starting to learn Java 

Hopefully, I will one day actually be able to make anything other than "Hello World" work.