Enum Category 

pub enum Category {
    DeclAdded,
    DeclRemoved,
    InterfaceRenamed,
    InterfaceRetired,
    MemberReordered,
    InteractionAppended,
    InteractionInserted,
    InteractionReordered,
    InteractionRemoved,
    InteractionRetired,
    KindChanged,
    PayloadChanged,
    ReturnChanged,
    ParamsChanged,
    TimingChanged,
    RpcBoundChanged,
    ContractChanged,
    WidthChanged,
    ConstraintChanged,
    InitChanged,
    ReservedNameRedeclared,
    ServiceChanged,
    ServiceInterfaceAdded,
    ServiceInterfaceRemoved,
    DocOnly,
    VisibilityChanged,
}

The kind of a single difference. The walk emits the structural categories; the classifier maps them to directional verdicts.

Variants

DeclAdded

A package-level declaration, interface, or service present only in the new snapshot.

DeclRemoved

A package-level declaration, interface, or service present only in the old snapshot. An interface is matched by its interfaces.lock number (lock design §7), so an interface here is one whose number is gone from the new snapshot and not retired there.

InterfaceRenamed

An interface whose interfaces.lock number is the same on both sides and whose name changed (lock design §7). The number is the interface’s identity and its routing key, so nothing moves on the wire; a rename is visible in source — it changes the generated identity-table names in both wire backends — so the text report lists it under the heading (heading). The path carries the new name; the detail carries the old and the new name.

InterfaceRetired

An interface whose number the old snapshot held and the new snapshot’s retired entries list (lock design §7): the sanctioned removal of an interface, recorded by ridl lock --retire.

MemberReordered

A surviving composite member whose slot in the body changed — a struct field, enum value, enum-set bit or union arm — reported only when both bodies hold the same member names. For a struct field or union arm the slot is the ordinal, which is wire identity (typl §7.4), and the detail carries the old and new ordinal. An enum value or enum-set bit carries an explicit number instead (typl §8, §9), but the walk compares positions, not those numbers, so a textual reorder of an enum or enum-set body is reported the same way, conservatively, even when no number changed; its detail carries the old and new position.

InteractionAppended

A new interaction added at the end of an interface (no earlier interaction shifted).

InteractionInserted

A new interaction added before the end — an earlier interaction now sits after it (ridl §11: insert shifts ordinals, a wire break).

InteractionReordered

A surviving interaction whose relative order within the interface changed (ridl §11: reorder shifts ordinals, a wire break).

InteractionRemoved

An interaction removed without leaving a reserved tombstone.

InteractionRetired

An interaction removed and replaced by a reserved tombstone in the same slot (ridl §11).

KindChanged

A surviving interaction whose kind changed (signal ↔ event, etc.).

PayloadChanged

A signal/event/fixed payload type changed.

ReturnChanged

A query return type changed.

ParamsChanged

A command/query parameter list changed.

TimingChanged

A signal/event resolved timing changed.

RpcBoundChanged

A command/query declared RPC bound changed (ADR-0015 decision 8). Separate from Category::TimingChanged because the direction of min inverts: on an RPC it constrains the caller, not the provider, so the signal/event rule must not be inherited silently.

ContractChanged

A command/query require/ensure clause set changed.

WidthChanged

A derived wire width or scalar backing changed.

ConstraintChanged

A scalar constraint (range, step, length, pattern) changed, or a composite member changed in place.

InitChanged

A resolved or declared init value changed.

ReservedNameRedeclared

A name that was a reserved tombstone is live again — an interaction inside an interface body.

ServiceChanged

A service switched between the named list and an inline shape. Narrowed to the form switch by ADR-0015 decision 19: a changed list is read as a set by the two ServiceInterface* categories below.

ServiceInterfaceAdded

An interface in a service’s set that the old snapshot’s set did not hold (ADR-0015 decision 19 as amended on 2026-09-15: a service’s list is a set of interface references).

ServiceInterfaceRemoved

An interface the old snapshot’s set held that the new one does not. Compatible on the wire — the routing key does not contain the service — and visible in source, so the text report lists it under that heading (heading).

DocOnly

Only doc comment, labels, or deprecation metadata changed.

VisibilityChanged

The visibility a declaration is published at changed. Separate from Category::DocOnly because internal removes the declaration from every out-of-package consumer (ADR-0002 §8), so the change has a direction.

Trait Implementations

impl Clone for Category

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 Category

impl Debug for Category

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

Formats the value using the given formatter.

impl Eq for Category

impl Hash for Category

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Category

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for Category

fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Category