Enum Arity 

pub enum Arity {
    One,
    Many,
}

Edge cardinality of a ConvergencePointType’s input or output.

Typed projection used by ConvergencePointType::input_arity and ConvergencePointType::output_arity so DAG composition validators reach for a closed-set enum rather than re-deriving the in/out cardinality from variant names. Many is the “≥1, could be N” cardinality — it carries no upper bound because the convergence point’s variant tag is already the structural identity; the number itself is a runtime property of the DAG, not the typescape.

Variants

One

Single edge — exactly one input or one output.

Many

Multiple edges — any number ≥ 1.

Implementations

impl Arity

pub const ALL: [Self; 2]

The closed set of arities — single source of truth that drives as_str / Display AND the is_one predicate. Adding a third variant (e.g. Arity::Zero for sinks) lands at one ALL entry + one as_str arm + one predicate arm — exhaustively checked by the compiler.

pub const fn as_str(self) -> &'static str

Canonical projection — "One" | "Many". Pinned by arity_display_matches_as_str so a future Display impl can’t drift from the canonical string.

pub const fn is_one(self) -> bool

Is this the single-edge cardinality? Closed-set match (not matches!) so a future variant triggers the compiler’s exhaustiveness check.

Trait Implementations

impl Clone for Arity

fn clone(&self) -> Arity

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Arity

impl Debug for Arity

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

Formats the value using the given formatter.

impl Display for Arity

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

Formats the value using the given formatter.

impl Eq for Arity

impl Hash for Arity

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 Arity

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Arity