static-atom.rs

enum Product {
    "BTC-EUR",
    "ETH-EUR",
    "ETH-BTC",
}

let p: Product = Product!("BTC-EUR");

mod product {
    struct "BTC-EUR";
    struct "ETH-EUR";
    struct "ETH-BTC";
  
    impl Convention for "BTC-EUR" {
        fn tick_size() -> f64 {
            0.01
        }
    }
}

struct Visitor {
    fn visit<C: Convention>() -> i32 {
        -C::tick_size().log10() as i32
    }
}

assert_eq!(2, product::visit_convention("BTC-EUR", Visitor));