Enum Builtin 

pub enum Builtin {
    Container,
    Label,
    Button,
    Toggle,
    Slider,
    TextField,
    TextArea,
    Picker,
    Divider,
    Scroll,
    Image,
    Progress,
    Canvas,
    Nav,
    NavPage,
    NavMenu,
    Tabs,
    TabsPage,
    List,
    ListCell,
    Cover,
}

Every piece kind Day itself defines (§5.3). Backends match on this exhaustively in realize; anything outside it is an extension piece resolved through the Registry by its string PieceKind.

Variants

Container

A dumb native panel (the column/row/stack backing).

Label

Button

Toggle

Slider

TextField

TextArea

A native multi-line text editor (docs/textarea.md). Built-in since 2026-07 (previously the satellite day-piece-textarea).

Picker

A native option picker with menu/segmented/inline stylings (docs/picker.md). Built-in since 2026-07 (previously the satellite day-piece-picker).

Divider

Scroll

Image

Progress

Progress indicator: determinate bar (fraction) or indeterminate spinner.

Canvas

Nav

Navigation host (docs/navigation.md): stack on mobile, split panes on desktop.

NavPage

One destination’s native container inside a NAV host.

NavMenu

Native navigation item list (docs/navigation.md): NSOutlineView source list / GtkListBox navigation-sidebar / QListWidget / UITableView rows with chevrons.

Tabs

Native tabbed container (docs/tabs.md): NSTabView / GtkNotebook / QTabWidget / UITabBarController / Android tab strip. Holds TABS_PAGE children, one visible.

TabsPage

One tab’s content container inside a TABS host; its frame is native-owned.

List

Native recycling list (docs/list.md): NSTableView / UITableView / RecyclerView / GtkListView / QListView. Owns scrolling + cell reuse; Day binds row content on demand.

ListCell

A recycled row’s content anchor inside a LIST; Day adopts the native cell as its handle. ADOPTED, never realized — Toolkit::adopt wraps the native cell, so backends’ realize never sees this kind.

Cover

A fullscreen cover (docs/cover.md): a modal surface presented over the whole window, edge-to-edge, driven by CoverPatch::{Present,Dismiss}. The handle is the cover’s CONTENT container; its frame is native-owned while presented (the backend sizes it to the safe area and reports it via Event::FrameChanged).

Implementations

impl Builtin

pub const ALL: &'static [Builtin]

Every built-in, in declaration order (conformance tests iterate it).

pub const fn key(self) -> PieceKind

This kind’s wire key — the same string as the matching kinds::* constant.

pub fn from_key(kind: PieceKind) -> Option<Builtin>

The built-in this key names, or None for an extension piece’s kind.

Trait Implementations

impl Clone for Builtin

fn clone(&self) -> Builtin

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Builtin

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Hash for Builtin

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Builtin

fn eq(&self, other: &Builtin) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Builtin

impl Eq for Builtin

impl StructuralPartialEq for Builtin