Hi,

I'm coming from C and some C++ so the way D stores class instance variables is new to me. If I'm not mistaken the basic unadorned instance variable is like a "hidden" pointer. So, when passing class instance variables to a function, what would be the point of passing a pointer or ref?

I think I answered myself, in that they'd would be pointers or references to the variable that holds the... hidden pointer to the class instance.

Now I'm unsure. When I pass a class instance to a function by value, I'm not creating a copy of the instance, am I?

Thanks,
Ian

On Saturday, 28 September 2024 at 18:16:55 UTC, Ian wrote:

An instance of a class is, of course, an object. The instance's variables can be int's or float's or struct's. Values. The instance has storage right there to hold the value.

An instance can also reference another class instance. Then, underneath, that's a pointer.

I think I see you assuming that how an instance variable treats values is different from how a local variable or a struct field would treat a value. My experience is they're all the same. The important difference between struct and class instance is that structs want to be values, and you have to go to extra trouble to work with pointers thereof. Instances want to be references, and you have to go to trouble (shallow or deep copy, presumably) if you want to get a value copy. But all this applies equally to instance variables and a struct's fields.

No you aren't.

(Now let the much deeper Dlang minds sweep in and correct me.)