Confusing Listings on section 5.1 due to the scope of the struct

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URL to the section(s) of the book with this problem:

https://doc.rust-lang.org/book/ch05-01-defining-structs.html

Description of the problem:

I found the Listings on this section a bit confusing to follow because it is unclear on which scope the struct is being defined.

Listing 5-1 is an example of a struct definition:

struct User {
    username: String,
    email: String,
    sign_in_count: u64,
    active: bool,
}

Which then is used on Listing 5-2 to create an instance of the struct User:

    let user1 = User {
        email: String::from("[email protected]"),
        username: String::from("someusername123"),
        active: true,
        sign_in_count: 1,
    };

When I followed this example I put both the struct definition and the creation of user1 in the main function body. Since then, I noticed that the code from Listing 5-1 is not indented suggesting that it is intended to be placed outside the main function, but I think this should may be included in the text.

That on itself is not an issue, since main() is the only function used in these examples. In fact Listing 5-3 is:

    let mut user1 = User {
        email: String::from("[email protected]"),
        username: String::from("someusername123"),
        active: true,
        sign_in_count: 1,
    };

    user1.email = String::from("[email protected]");

Which, as far as I understand, is intended to be included in the main function body, since there's no mention of any other function.

My problem is with Listing 5-4:

fn build_user(email: String, username: String) -> User {
    User {
        email: email,
        username: username,
        active: true,
        sign_in_count: 1,
    }
}

This code follows immediately after Listing 5-3, but it won't work if the struct definition is defined in the main function scope (as Listing 5-3 suggest we do). After following this examples I had the following code:

fn main() {

    struct User {
        username: String,
        email: String,
        sign_in_count: u64,
        active: bool,
    }

}

fn build_user(email: String, username: String) -> User {
    User {
        email: email,
        username: username,
        active: true,
        sign_in_count: 1,
    }
}

Which didn't work because User is not defined in the scope of build_user. I think this can be confusing for new users since the compiler shows the error: cannot find type `Users in this scope and scopes haven't been explained yet at this point in the book.

Suggested fix:

A small sentence explaining in which scope the struct definition should go or including the entire code (with the main() {} definition) should make things clearer.

[arcAman07]

Hey guys can I take up this issue

[carols10cents]

No thank you, I'd like to think about it and take care of it. Thanks though!