Struct ImplTraitBoundary 

pub struct ImplTraitBoundary { /* private fields */ }

An impl-trait boundary: a module’s public API must not return a written impl Trait (return-position impl Trait / RPIT). The existential complement of DynTraitBoundary: where that forbids the dynamic-dispatch shape (dyn), this forbids the existential shape — an unnameable type the caller cannot name, store without boxing, or rely on beyond its declared bounds. Governs return positions only: argument-position impl Trait (APIT) is universal (a caller-chosen generic), not an existential leak, and is never governed; async fn’s implicit impl Future is a distinct compiler-inserted existential, out of scope. Declared in Rust and composed with the other dimensions at the gate.

Two depths on one boundary type, selected by the builder (mirroring DynTraitBoundary):

• must_not_expose_impl_trait — shape-only: an empty operand set, so any returned impl Trait reacts.
• must_not_expose_impl_trait_of — operand-scoped: only a returned impl Trait whose principal trait resolves into the named forbidden_operands set reacts.

Implementations

impl ImplTraitBoundary

pub fn in_crate(package: &str) -> ImplTraitCrateDraft

Begin an impl-trait boundary in the crate named package.

pub fn crate_package(&self) -> &str

The crate this boundary governs.

pub fn module(&self) -> &str

The governed module path (e.g. crate::core).

pub fn forbidden_operands(&self) -> &[String]

The forbidden trait operands. Empty ⇒ shape-only (any returned impl Trait reacts); a named set ⇒ only a returned impl Trait whose principal trait resolves into the set reacts.

pub fn reason(&self) -> &str

The human-readable reason recorded with the boundary (the repair hint).

pub fn with_anchor(self, anchor: &str) -> Self

Attach a durable governance anchor (e.g. "ADR-014") — a stable pointer into the project’s governance, distinct from the free-text reason. Optional; a boundary with none projects and reacts exactly as before.

pub fn anchor(&self) -> Option<&str>

The durable governance anchor recorded with the boundary, if any.

pub fn severity(&self) -> Severity

The boundary’s severity (enforce or warn).

Trait Implementations

impl Clone for ImplTraitBoundary

fn clone(&self) -> ImplTraitBoundary

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ImplTraitBoundary

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

Formats the value using the given formatter.

impl Eq for ImplTraitBoundary

impl PartialEq for ImplTraitBoundary

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ImplTraitBoundary