I am also a noob. But I think the slice.eq(something_else) is using a trait functionality. And the Eq trait is listed in the trait section (below the methods) in the link you provided.

Here is the link to that spot on the page:
https://doc.rust-lang.org/std/primitive.slice.html#impl-Eq

Honestly fantastic! I am of young-coding-age, and this exercise was quite some work for me. (My solution looks very verbose and confusing aswell)
Your version seems very smart ANS is really sweet to follow. Great job! (I think)
Thanks for this

verbose like a boss