Rust error E0574: expected struct, variant or union type, found module `mordor`

The compiler team's explanation

Something other than a struct, variant or union has been used when one was expected.

Erroneous code example:

mod mordor {}

let sauron = mordor { x: () }; // error!

enum Jak {
    Daxter { i: isize },
}

let eco = Jak::Daxter { i: 1 };
match eco {
    Jak { i } => {} // error!
}

In all these errors, a type was expected. For example, in the first error, we tried to instantiate the mordor module, which is impossible. If you want to instantiate a type inside a module, you can do it as follow:

mod mordor {
    pub struct TheRing {
        pub x: usize,
    }
}

let sauron = mordor::TheRing { x: 1 }; // ok!

In the second error, we tried to bind the Jak enum directly, which is not possible: you can only bind one of its variants. To do so:

enum Jak {
    Daxter { i: isize },
}

let eco = Jak::Daxter { i: 1 };
match eco {
    Jak::Daxter { i } => {} // ok!
}

From rustc --explain E0574 (1.99.0), part of the Rust project, MIT or Apache-2.0. Official page.