Struct PathPattern 

pub struct PathPattern { /* private fields */ }

Path pattern matcher.

Matches paths against a sequence of steps, supporting variable-length patterns and filters.

Example

// Pattern: (a)-[:KNOWS]->(b)-[:WORKS_AT]->(c)
let pattern = PathPattern::new()
    .add_step(PathStep::outgoing("KNOWS"))
    .add_step(PathStep::outgoing("WORKS_AT"));

let matches = pattern.find_from(&tx, start_node)?;

// Variable-length: (a)-[:FRIEND*1..3]->(b)
let pattern = PathPattern::new()
    .add_step(PathStep::outgoing("FRIEND").variable_length(1, 3));

Implementations

impl PathPattern

pub fn new() -> Self

Create a new empty pattern.

pub fn add_step(self, step: PathStep) -> Self

Add a step to the pattern.

pub fn outgoing(self, edge_type: impl Into<EdgeType>) -> Self

Add an outgoing step with the given edge type.

pub fn incoming(self, edge_type: impl Into<EdgeType>) -> Self

Add an incoming step with the given edge type.

pub fn both(self, edge_type: impl Into<EdgeType>) -> Self

Add a bidirectional step with the given edge type.

pub const fn with_limit(self, limit: usize) -> Self

Set the maximum number of matches to return.

pub const fn allow_cycles(self) -> Self

Allow cycles in matched paths.

By default, nodes cannot be visited more than once in a path.

pub fn steps(&self) -> &[PathStep]

Get the steps in this pattern.

pub fn is_empty(&self) -> bool

Check if this pattern is empty.

pub fn find_from<T: Transaction>( &self, tx: &T, start: EntityId, ) -> GraphResult<Vec<PatternMatch>>

Find all paths matching this pattern from a starting node.

pub fn find_between<T: Transaction>( &self, tx: &T, start: EntityId, end: EntityId, ) -> GraphResult<Vec<PatternMatch>>

Find paths matching this pattern that end at a specific node.

pub fn matches<T: Transaction>( &self, tx: &T, start: EntityId, ) -> GraphResult<bool>

Check if any path matches this pattern from the given start.

Trait Implementations

impl Clone for PathPattern

fn clone(&self) -> PathPattern

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PathPattern

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

Formats the value using the given formatter.

impl Default for PathPattern

fn default() -> PathPattern

Returns the “default value” for a type.