lyric fog
https://pedropark99.github.io/zig-book/Chapters/10-stack-project.html
(e.g. code at https://github.com/pedropark99/zig-book/blob/main/ZigExamples/data-structures/stack.zig#L20)
On this page they make a simple generic struct. I don't understand why the self: *Self needs to be a pointer type, but if it isn't a pointer, I get 'cannot assign to constant' in the methods.
I see the same in the std lib ArrayList, I wonder if it's like Go when you need a pointer receiver to modify self?
coarse raft
if self isn't a pointer, it's passed by value. so if zig allowed self.length += 1, it would update length from 3 to 4, return from the function, and the caller would still see .length as 3. by making it a pointer, it doesn't copy it