[reference] Reduce reading ambiguity

[zcy1024]

Adjust the code according to the context of the article to reduce ambiguity.

[damirka]

should be option::some

[damirka]

Or add a use statement above.

[zcy1024]

The relevant use statement is below, which is what this example needs to demonstrate.

[damirka]

Why did you remove Option type import?

[zcy1024]

As far as I understand, use inside a function body is not effective during the function declaration. The previous writing method does not report an error because std::option::Option is imported by default. I made this change to make that clear.

Of course, I just made the changes based on my understanding. If my understanding itself is wrong, please correct me.

[zcy1024]

To illustrate further, I wrote a small example:

module examples::a {
    public struct MyOption<T> has copy, drop, store {
        vec: vector<T>
    }

    public fun some<T>(e: T): MyOption<T> {
        MyOption {
            vec: vector[e]
        }
    }

    public fun none<T>(): MyOption<T> {
        MyOption {
            vec: vector[]
        }
    }
}

module examples::b {
    // If you replace the two commented lines below, you will get an error.
    // fun new_vec(): vector<MyOption<u8>> {
    //     use examples::a::{MyOption, some, none};
    fun new_vec(): vector<examples::a::MyOption<u8>> {
        use examples::a::{some, none};

        let mut v = vector[];
        v.push_back(some(0));
        v.push_back(none());
        v
    }
}