// Created on savesnippets.com · https://savesnippets.com/gj4xu5TLKqijFy
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
struct UserId(u64);

#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
struct PostId(u64);

fn delete_user(id: UserId) {
    println!("deleting user {}", id.0);
}

fn main() {
    let u = UserId(42);
    let p = PostId(99);

    delete_user(u);        // ✓
    // delete_user(p);     // ❌ mismatched types: expected UserId
    // delete_user(42);    // ❌ expected UserId, got integer
}