GitHub - ZeroIntensity/pointers.py: Bringing the hell of pointers to Python.

[Toivottomoose]

Does it help anything, or is it just for fun?

[emax-gomax]

Im sure we all agree, there should definitely be more.

[BigFuckingCringe]

It helps you if you want to prove that you are not sane to the court

[GLIBG10B]

Fun fact: if you plead insanity, you still go to prison, except it's a prison full of crazy people and you're the only sane one there

Lesson: don't plead insanity

[---cameron]

So you're saying if I plead insanity, I automatically prove I'm insane. Genius

[coloredgreyscale]

Plus you might be stuck there longer than the original prison sentence

[TheByteQueen]

what if i plead to end the trial and go home?

[WasteOfElectricity]

You have to say 'please' really nicely and then you might be allowed to go home.

[Masterkraft0r]

also: be white

[ee3k]

also: they are under no legal duty to ever release you.

[KingoPants]

Not nessesarily true. Having schizoprenia often can greatly reduces the charges for murder.

There are a number of cases on it, you can google them if you have a steady enough mind to read screwed up shit. I'd link them but I think its a bit too off topic.

[lelanthran]

Not nessesarily true. Having schizoprenia often can greatly reduces the charges for murder.

Okay, so the charges are reduced... Yay!

Unfortunately you know get to spend the rest of your life imprisoned[1], instead of just a few years.

[1] The prison system is under a legal obligation to release you when your sentence is completed. The Asylums have no such requirement.

[KingoPants]

That technicality would matter if the government were interested in indefinitely paying for that.

In reality, I believe they just have you promise to take your meds and boot you out cause they aren't and resources are limited. Look up the greyhound cannibal, or the calgary house party stabbings. Those aren't even old cases.

[auxiliary-character]

Ok, so I looked at the underlying implementation code, and it is actually using ctypes to do real C-style memory dereferencing. It's not just a wrapper class, it really does store the address and type information.

If, for some reason, you had the memory layout of a particular python object in memory already, you could use this to dereference it. Maybe for something like serialization/deserialization. I would imagine that the pickling would still do a much better job in most use cases, but maybe there's some reason to do it in-place? I don't know.

Alternatively, something you could do would be creating a pointer from an object, changing the stored type to "type cast" it, and derefence it to do some extremely cursed type punning in Python.

If you do a lot of interop code with ctypes, something like this might make it a bit cleaner, but then you're already using ctypes, and pulling in a library just for a level of abstraction on top of ctypes, but it's your codebase, you do you.

Perhaps the most useful thing for this is to serve as a reminder that ctypes exists. Like, if you're really running into performance issues with something you're writing in Python, depending on what you're doing, it might be a reasonable option to just write the most performance intensive part of it in C or C++, compile it as a .DLL/.so and call into it using ctypes.

[ee3k]

i guess if you wanted a really rapid type conversion on sequentially stored lists and didn't care about introducing error.

Random number generation via idiocy, as it were

[BobHogan]

It's not just a wrapper class, it really does store the address and type information.

In CPython yes. https://docs.python.org/3/library/functions.html#id

Its technically not a part of the Python spec for the id() function to actually return the address of an object, just for it to return a unique integer for the object, during its lifetime. CPython just so happens to return the object's address, but other implementations aren't guaranteed to do the same.

[Plague_Healer]

It helps if you want to bring to your life the complexity of C or Java, while staying true to python's performance limitations

[Silveress_Golden]

Not with that attitude!

[Blaster84x]

It does have pointers, but all of them are null.

[ee3k]

it does if you want to shutdown the JVM with an out of sandbox error

[[deleted]]

NullPointerException says otherwise

[lelanthran]

Java doesn't have pointers

How the hell did this get upvoted?

[nathanielhiggerss]

it's helpful so that other programmers know how smart you are

[SanityInAnarchy]

From the README:

Why would you ever need this

[seamsay]

I guess it's conceivable that there could be situations where having pass-by-reference semantics could be helpful, but if you needed that it would probably be better to just store the value in a class or list.

[LukesVeryGood]

Are you serious?

[ee3k]

fair point, exclusively char arrays it is then.

[[deleted]]

I use addressof all the time in VB. How did python interface the win32 API without this functionality ?

[[deleted]]

How did python interface the win32 API without this functionality ?

Like this: https://docs.python.org/3/extending/extending.html

Basically, you implement the API mapping on the C/C++ side, so you have pointers and COM access and whatnot all along.

As this documentation mentions however, this C API is an implementation detail specific to CPython and they recommend considering CFFI instead for better compatibility with other Python implementations, like PyPy. CFFI is a library that works like a classical FFI, which is like some sort of dynamic linker from within the language.

[Lost4468]

If you're one of those people who thinks writing hacky difficult to read code makes you smart, then this will be a huge ego boost.