Enum PropertyConstraintKind 

pub enum PropertyConstraintKind {
    Unique,
    NotNull,
    PropertyType(PropertyType),
    NodeKey,
}

Kind of single-property constraint. Unique comes from REQUIRE n.prop IS UNIQUE, NotNull from REQUIRE n.prop IS NOT NULL, and PropertyType(t) from REQUIRE n.prop IS :: <TYPE>. PropertyType carries the target type so a single constraint-kind enum covers all four flavours without blowing up into one variant per type.

Variants

Unique

NotNull

PropertyType(PropertyType)

NodeKey

REQUIRE (n.a, n.b) IS NODE KEY — composite uniqueness + NOT NULL. The constraint holds across the tuple of values the spec’s properties list names; each property must be present and the tuple must be unique across every node carrying the constrained label.

Implementations

impl PropertyConstraintKind

pub fn as_string(&self) -> String

Short, human-facing token used in SHOW CONSTRAINTS output. For PropertyType the string carries the target type inside parentheses so operators reading the output can see what the constraint enforces at a glance. Stable — do not rename without a migration, because the auto-name the storage layer derives from this tag is part of the user-visible DROP surface.

pub fn name_tag(&self) -> String

Lowercase tag used when generating a default constraint name. PropertyType(T) contributes type_<t> so every distinct type gets its own auto-name and two type constraints on the same (label, property) can coexist if they ever need to.

pub fn allows_multi_property(&self) -> bool

True iff the kind accepts more than one property in its spec. Used by the storage layer to validate the properties list length at create time — single-property kinds must not receive a multi-element list.

Trait Implementations

impl Clone for PropertyConstraintKind

fn clone(&self) -> PropertyConstraintKind

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PropertyConstraintKind

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

Formats the value using the given formatter.

impl Hash for PropertyConstraintKind

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 PropertyConstraintKind

fn eq(&self, other: &PropertyConstraintKind) -> 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 Copy for PropertyConstraintKind

impl Eq for PropertyConstraintKind

impl StructuralPartialEq for PropertyConstraintKind