Enum DesignLanguage 

#[non_exhaustive]
pub enum DesignLanguage {
    Material3,
    Cupertino,
    Glyph,
    Custom(&'static str),
}

Which design language assembled a Theme — a Theme itself stays a single, language-agnostic aggregate struct; this is just a tag app/shell code can branch on (e.g. to pick per-platform interaction affordances), not a second Theme type. No constructor in this crate produces anything but the derived default: a design system sets its own tag through ThemeBuilder::design_language while assembling its baseline, from its own crate.

The tag is identity, not behavior: a design system styles itself entirely via Theme‘s tokens plus Theme::extensions (see ThemeExtensions) — this enum just lets a host/widget recognize which system is active, or deliberately ignore an unrecognized one. #[non_exhaustive] and Custom together mean a new built-in variant, or a third-party system tagging itself, is never a breaking change for downstream code: the built-in ==-based branch site (frust-widgets’ slider) already treats anything that isn’t Cupertino as the neutral path by construction, so an unrecognized Custom id falls through safely. Two Custom tags compare equal by string content, not by pointer/interning identity.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Material3

Material 3 (Android/cross-platform baseline). Default — the tag Theme::neutral carries for want of a neutral variant (see that constructor’s caveat), and the one frust-material sets explicitly.

Cupertino

Cupertino (iOS) — the tag frust-cupertino sets.

Glyph

Glyph — the tag frust-glyph sets.

Custom(&'static str)

A third-party design system’s identity tag — the id is the system’s stable name (e.g. "yaru"). Carried so hosts/widgets that branch on language can recognize (or deliberately ignore) an external system; the built-in == branch site (the slider) treats any Custom as the neutral path by construction. Compared by string content — Custom("yaru") == Custom("yaru") even across two distinct &'static str allocations with the same bytes.

Trait Implementations

impl Clone for DesignLanguage

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for DesignLanguage

impl Debug for DesignLanguage

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

Formats the value using the given formatter.

impl Default for DesignLanguage

fn default() -> Self

Returns the “default value” for a type.

impl Eq for DesignLanguage

impl PartialEq for DesignLanguage

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for DesignLanguage