Design of component children

[pepsighan]

Currently component children is not supported. The target design which I am striving for here is inspired/taken from vuejs (slot system).
The design demands the following requirements:

1. The slots are rendered in the context where it is written. The fields & methods of the component is accessible to the slot but not of the child component.

...
struct MyApp { ... }

impl MyApp {
  fn on_click(&self, _: Event) {}
}

impl Render for MyApp {
  fn render(&self) -> Markup<Self> {
    html! {
      <Content>
        { self.prop_a }
        <button @click={Self::on_click}>Click</button>
        // But cannot access Content.do_something
      </Content>
    }
  }
}

...
struct Content { ... }

impl Content {
  fn do_something(&self) {}
}

impl Render for Content {
  fn render(&self) -> Markup<Self> {
    html! {
      <div>
        <slot></slot>
      </div>
    }
  }
}

2. Slots are functional which accept arguments from their children aka Scoped Slots.

3. There can be any number of named slots.