Rename `use_either_n` feature and add documentation

[plul]

Say I have two pages, and I want some condition to determine which one is rendered.
Essentially, what I'm looking for is a way to write if/else inside the render function. (In Angular terminology, I'm looking for an *ngIf equivalent). The docs and examples do not cover this.

The following example illustrates my best solution at present, using a range and a filter. However, it feels hacky and I am wondering whether something cleaner is intended.

    let render_page1 = |state: &State| h1(("This is page 1"));

    let render_page2 = |state: &State| h2(("This is page 2"));

    let render = |state: &State| {
        div((
            button((on("click", |_| Msg::ToggleMyBoolean), "Toggle myBoolean")),
            (0..1)
                .filter(|_| state.myBoolean)
                .map(|_| render_page1(state))
                .collect::<Vec<_>>(),
            (0..1)
                .filter(|_| !state.myBoolean)
                .map(|_| render_page2(state))
                .collect::<Vec<_>>(),
        ))
    };

By the way, great work on this crate! It is quite fun to play with. Cheers!

[cramertj]

You can use the EitherN enums from the either-n crate for this. Here's a test showing how.

Glad you're having fun playing around-- let me know if you have any other questions.

[cramertj]

Note to self: rename the use_either_n feature to just either_n so that it will automatically be included when users import the either_n crate.

[cramertj]

I'm actually going to reopen this until I've renamed the feature and added examples.

[plul]

This will do. Thanks!

(It does not work if I write #[cfg(feature = "use_either_n")], but if I omit it, everything works).

[cramertj]

@plul Yeah, use_either_n is a default feature of Domafic-- it's not something you'd cfg in your code.

[plul]

Using your either_n solution works great if I want to render one page or the other, but does domafic support some kind of None tag?

Say I want to do this:

if myCondition {
    either_n::Either2::One(div("Hello"))
}
else {
    either_n::Either2::Two(None)
}

I could of cause just do either_n::Either2::Two("") - it will just leave some empty <span>s here and there.