How do I build a graph from patterns?

StandardGraph interprets Pattern<Subject> elements as graph elements (nodes, relationships, walks). The easiest way to populate it is directly from a Gram notation string.

Rust

use gram_codec::FromGram;
use pattern_core::StandardGraph;

let graph = StandardGraph::from_gram("(alice:Person)-[:KNOWS]->(bob:Person)")?;

println!("nodes: {}", graph.node_count());
println!("relationships: {}", graph.relationship_count());

Python

from relateby.pattern import StandardGraph

graph = StandardGraph.from_gram("(alice:Person)-[:KNOWS]->(bob:Person)")

print(f"nodes: {graph.node_count()}")
print(f"relationships: {graph.relationship_count()}")

TypeScript

import { StandardGraph } from "@relateby/pattern"
import { Effect } from "effect"

const graph = await Effect.runPromise(
  StandardGraph.fromGram("(alice:Person)-[:KNOWS]->(bob:Person)")
)

console.log(`nodes: ${graph.nodeCount}`)
console.log(`relationships: ${graph.relationshipCount}`)

See also: When should I use Pattern versus a plain graph library?