Struct Guard 

pub struct Guard {
    pub origin: Origin<ItemConst>,
}

An anonymous const: const _: T = .., whatever produced it.

The definition is the shape, not the origin. A const with no name has no address, so nothing can declare it, reference it, or emit it as an alias — which is what puts it outside the flat API rather than in it, and that holds however the item arrived: synthesized, hand-fed to FlatBuilder, or written as #[prebindgen] const _: () = .. in a source crate.

Today’s producer is Source’s cfg filter, which synthesizes const _: () = { konst::assertc_eq!(..) } to assert that a source crate’s FEATURES match what the build script asked for. Nothing marked that one — it is prebindgen’s own item riding the same stream — but it is not the only thing that can land here, and the model does not claim otherwise.

Cardinality is zero or more. enable_feature_filtering(None) produces none, and each item iterator taken from a Source emits its own, so composing two iterators from one crate yields two.

It carries no type, unlike a Constant. The item is emitted verbatim, so what its types mean is the consumer crate’s business; modelling them would let a guard that names something undeclared refuse the whole element.

Fields

origin: Origin<ItemConst>

Emitted verbatim, so the item is all there is.

Trait Implementations

impl Clone for Guard

fn clone(&self) -> Guard

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Guard

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

Formats the value using the given formatter.