Assert to confirm a single rust variant

I have a function that takes an enum parameter and I wish to use an assert macro that panics for all but one of the enum variants. What is the best way to do this?

To illustrate--- In the following code example, I'm looking for a way to write an assert macro I can place at the top of the "want_a_bar" function, that avoids the need for the noisier match statement. My attempts at this all seem to run into various problems and I'm hoping there is an obvious solution I am missing.

enum Foo {

fn want_a_bar(foo: Foo) {
    match foo {
        Foo::Bar(_) => println!("All good here!"),
        _ => panic!("Expected a Bar got something else.")

fn main() {
    let foo = Foo::Bar(8);

How about assert!(matches!(foo, Foo::Bar(_)))?


Thank you. That does it!