Function visit_diff::all_different

pub fn all_different<T: ?Sized>(a: &T, b: &T) -> bool where
    T: Diff, 

Checks if there is something different about every top-level part of a and b. For example, if every field of two structs has some difference.

The individual parts are compared using any_difference.

This is used to adjust the granularity of diff reporting by debug_diff: it will show compound types (like structs) as different at the top level if they are all_different, or diff individual fields if not.

use visit_diff::{Diff, all_different};

#[derive(Diff, Debug)]
struct ExampleStruct {
    name: &'static str,
    age: usize,
}

let left = ExampleStruct { name: "Bob", age: 4 };
let right = ExampleStruct { name: "Rototron 3k", age: 4 };

assert_eq!(
    all_different(&left, &right),
    false,
    "Bob and Rototron have few things in common, but they're the same age.",
);

let right = ExampleStruct { age: 5, ..right};  // if we change the age...
assert_eq!(all_different(&left, &right), true);