Trait KeymapReverseLookup 

pub trait KeymapReverseLookup: Send + Sync {
    // Required method
    fn chords_for(&self, command_name: &str) -> Vec<KeyChord>;

    // Provided method
    fn chords_with_source(
        &self,
        command_name: &str,
    ) -> Vec<(KeyChord, KeybindingSource)> { ... }
}

Reverse-lookup contract the keybinding annotator depends on: given a command’s canonical name, return the chord sequence(s) bound to it. Empty vec means “no binding.”

MARG.2 (2026-06-03): the lattice-host side maintains the reverse cache (built alongside the merged keymap trie on every bind / unbind) and supplies an implementor at boot. Keeping the trait in lattice-completion lets the annotator type live with the other annotators while leaving the cache-build / invalidation logic in the host crate where the trie lives.

The empty-vec contract is important: KeybindingAnnotator short-circuits on empty results so commands without a bound chord don’t get a misleading empty annotation. Implementors should NOT return vec![] to mean “lookup failed” — return it to mean “no binding,” same thing semantically.

MARG.3 (2026-07-15): chords_with_source returns structured provenance alongside each chord so callers can filter by active modes and display the source mode label. The default impl wraps every chord from chords_for with KeybindingSource::AlwaysOn — implementors that maintain mode-aware caches (e.g. the host’s keymap registry) should override this to return the real provenance.

Required Methods

fn chords_for(&self, command_name: &str) -> Vec<KeyChord>

Provided Methods

fn chords_with_source( &self, command_name: &str, ) -> Vec<(KeyChord, KeybindingSource)>

Like chords_for but returns each chord tagged with its KeybindingSource so callers can filter by active mode and display provenance.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors