Struct Slots 

pub struct Slots { /* private fields */ }

The children a component receives from its call site, grouped by slot. A bare child lands in the default slot (None); a child written with slot:"name" lands in that named slot. Inside the component, the children placeholder drains the default slot and children name:"x" drains the "x" slot — each in call-site order. Draining is one-shot: a slot placeholder consumes its children, so referencing the same slot twice yields an empty list the second time.

Implementations

impl Slots

pub fn new() -> Self

pub fn push(&mut self, name: Option<&'static str>, item: Box<dyn LayoutItem>)

pub fn extend_default( &mut self, items: impl IntoIterator<Item = Box<dyn LayoutItem>>, )

Appends items as default (unnamed) children. What every generated component call site does with the children it collected, so the emitter writes one call instead of a hand-rolled loop 418 times over.

pub fn len(&self) -> usize

How many children are still undrained, across every slot.

pub fn is_empty(&self) -> bool

Whether the call site passed no children at all — what a compound component checks before falling back to whatever it shows when it was given nothing.

pub fn take_default(&mut self) -> Vec<Box<dyn LayoutItem>>

Drains the default (unnamed) children in call-site order.

pub fn take(&mut self, name: &str) -> Vec<Box<dyn LayoutItem>>

Drains the children assigned to the named slot name, in call-site order.

Trait Implementations

impl Default for Slots

fn default() -> Slots

Returns the “default value” for a type.

impl From<Slots> for Children

fn from(slots: Slots) -> Self

For a caller holding children it already built — a test, or a component forwarding what it was given. The recipe hands them out once and is empty on any later call, since a built widget cannot be made twice.