Scryer-prolog: Rust questions/issues

[notoria]

1. Why is &Vec<T> used in function argument instead of &[T]? Example in this line, it also occurs in other places.

2. Why is &Vec<T> used in the trait Allocator instead of &[T]? Line
   Does this mean this method can extend/shrink the last argument?

3. Are some types supposed to implement Copy? Like Addr which implements Copy but there are some clone operations.

[mthom]

1. That's a holdover from when I started this project. I was only beginning to learn Rust. I agree, there's no good reason not to pass a slice in those cases.

2. mark_var can push instructions into the last argument, yes.

3. Addr only recently implemented Copy. Consequently there are some still vestigial clone operations lying around.

[notoria]

OK and

Why is &Vec used in the trait Allocator instead of &[T]?

But even for trait Allocator &Vec<T> doesn't seem required, &[T] seem better.

This seems to be a good first issue.

[mthom]

Yes, there's no reason to prefer &Vec to &[T].