Struct ClassGroupBreakdown 

pub struct ClassGroupBreakdown { /* private fields */ }

A class-id-keyed slice axis: a name plus a list of ClassGroups.

The sibling of Breakdown for class-id partitions. Used by semantic (ADR-0041) and panoptic (ADR-0042) class_grouping fields. Carries strict partition discipline — no class id may appear in two groups.

Invariants (debug-checked at construction)

• groups is non-empty.
• Every ClassGroup::index is unique and lies in 0..groups.len().
• No class id appears in two groups (partition discipline).
• Group labels are unique.

Implementations

impl ClassGroupBreakdown

pub fn new(axis: impl Into<Cow<'static, str>>, groups: Vec<ClassGroup>) -> Self

Construct from an axis name and a list of groups.

Panics

In debug builds, panics if groups is empty, has duplicate / out-of-range indices, has duplicate labels, or has a class id appearing in two groups. Release builds silently accept the degenerate input — no memory safety risk under #![forbid(unsafe_code)].

pub fn axis(&self) -> &str

Axis name (e.g., "object_size", "vehicle_taxonomy").

pub fn groups(&self) -> &[ClassGroup]

All groups, in construction order.

pub fn len(&self) -> usize

Number of groups — the size of the group axis the summarizer emits one row per.

pub fn is_empty(&self) -> bool

true when Self::len is 0 (degenerate; only reachable in release builds with a malformed Self::new call).

pub fn group_at(&self, index: usize) -> Option<&ClassGroup>

Group at axis position index, or None if absent.

pub fn group_of(&self, class_id: u32) -> Option<&ClassGroup>

Look up the group containing class_id. None if no group covers it (partition allows un-grouped ids — they’re simply excluded from per-group rollups).

Trait Implementations

impl Clone for ClassGroupBreakdown

fn clone(&self) -> ClassGroupBreakdown

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ClassGroupBreakdown

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

Formats the value using the given formatter.

impl PartialEq for ClassGroupBreakdown

fn eq(&self, other: &ClassGroupBreakdown) -> 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 Eq for ClassGroupBreakdown

impl StructuralPartialEq for ClassGroupBreakdown