Struct ActiveModes 

pub struct ActiveModes { /* private fields */ }

The set of modes active on a buffer. Exactly one major (or none, prior to first major activation), plus any number of minors in activation order.

Ordering invariant: minors are stored in the order they were activated; when an active mode is deactivated, the survivors retain their relative positions (no reshuffling). This is what M.2’s option-resolution layer relies on for “later activation wins” tie-breaking.

SmallVec keeps the typical case (0-4 minors) inline. A buffer with more active minors spills to the heap; that’s fine – the hot path is option resolution against the cached ResolvedOptions, not iteration of ActiveModes.

Implementations

impl ActiveModes

pub fn new() -> Self

Construct an empty set (no major, no minors).

pub fn major(&self) -> Option<ModeId>

The active major, if any. None until the first major activation runs (e.g. a freshly-opened scratch buffer before mode resolution).

pub fn minors(&self) -> &[ModeId]

All active minors, in activation order.

pub fn keymap_gated_ids(&self) -> Vec<ModeId>

The mode ids the keymap lookup must gate on, in priority order: the active major first (lowest of the gated layers), then the minors in activation order (each overlaying the previous). Pass this to KeymapHandle::lookup_with_context so a MajorMode layer fires only in buffers where that major is active — a bare minors() slice would leave major-mode chords ungated (they’d fire everywhere).

pub fn has_minor(&self, mode: ModeId) -> bool

True iff this minor is currently active.

pub fn is_active_major(&self, mode: ModeId) -> bool

True iff mode is the active major.

pub fn is_active(&self, mode: ModeId) -> bool

True iff mode is active in any role (major or minor).

Trait Implementations

impl Clone for ActiveModes

fn clone(&self) -> ActiveModes

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ActiveModes

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

Formats the value using the given formatter.

impl Default for ActiveModes

fn default() -> ActiveModes

Returns the “default value” for a type.