Rust by example: The ref pattern

Question

I have problems understanding the ref pattern in Rust. I am referring to https://rustbyexample.com/scope/borrow/ref.html

Here is the code I don\'t under

Answer 1

A reference created with ref is exactly the same as reference taken with &.

The difference is where they're allowed in the syntax. ref on the left side of an assignment is like adding & on the right side.

These expressions are equivalent:

let ref x1 = y;
let x2 = &y;

This redundancy exists because in pattern matching & is used to require that a reference exists already, rather than to make a new one:

let foo = 1;
match foo {
   ref x => {
       /* x == &1 */ 
       match x {
           &y => /* y == 1 */
       }
   },  
}

(discussion)