Enum Children 

pub enum Children<'a> {
    None,
    One(&'a dyn Widget),
    Many(&'a [BoxedWidget]),
}

The render layer trait. Every built-in widget implements this.

Widget is the render/paint concern — layout + draw. It is NOT what users implement to compose UI; that’s rosace_core::Component. Custom widgets can implement Widget for low-level control. How a widget exposes its structure to the framework (D098).

This is the taxonomy: a leaf keeps the default (None), a single-child wrapper returns One, a container returns Many. Every Widget default below keys off this, so a wrapper only implements the one method it actually changes.

Variants

None

Leaf — draws content, has no children.

One(&'a dyn Widget)

Single-child wrapper — decorates or constrains one child.

Many(&'a [BoxedWidget])

Multi-child container — arranges several children.