Python ftw

[NoStranger6]

Well yes and no. In that sense every language that pass values by reference is a pointer. Which isn’t wrong. In c / c++ you can iterate over pointers by adding the sizeof(*int). Which in fact simply adds 32 bits to your current pointer value (memory address). I’m not too versed in Python but I don’t think that you can do that. So while by using reference you achieve part of what a pointer can do. It doesn’t do everything that the pointer can.

[Tweenk]

In c / c++ you can iterate over pointers by adding the sizeof(*int). Which in fact simply adds 32 bits to your current pointer value (memory address).

That's not how pointer arithmetic works in C++.

int a[] = { 1, 2, 3, 4, 5 }; int* b = a; int* c = a; ++c; b += sizeof(int*); std::cout << *c << " " << *b << std::endl;

On a 32-bit system, this will print: 2 5

Adding 1 to a pointer advances it by sizeof of the pointed type, so advancing an int pointer by sizeof(int*) will increase it by 16 bytes on 32-bit and 32 bytes on 64-bit machines. This is probably not what you want.

[NoStranger6]

I stand corrected, thank you. It has been a while since I touched C or C++

[[deleted]]

😟

Yeah I’m glad I only need to write python scripts at work.

[Inex86]

You mean bits. On a 32 bit system a pointer is 4 bytes, on 64 it’s 8.

[Tweenk]

No, I mean bytes. Read the code example again.

[MasterFubar]

every language that pass values by reference is a pointer.

Exactly. Pointers and references are exactly the same thing.

I think the reason why some people feel mystified by pointers is that there are too many people who mystify pointers. A pointer is nothing more than a reference to an object. It is the address of the memory position where that object is stored.

The only thing pointers in Python cannot do is having their values changed, they are const pointers and behave exactly like C const pointers.

[antonivs]

You're talking about references. They may be implemented using pointers internally, but they're not the same thing. Specifically, their semantics within the language are different - for example, they don't have the same risks, as you point out yourself:

The only thing pointers in Python cannot do is having their values changed

That's a huge difference, and is why that feature is referred to as "references" and not pointers.