Function heuristic

packages/effect/test/Graph.test.ts:2476–2477

(source: { x: number; y: number }, target: { x: number; y: number })

        })

        const heuristic = (source: { x: number; y: number }, target: { x: number; y: number }) =>
          Math.abs(source.x - target.x) + Math.abs(source.y - target.y)

        const result = Graph.astar(graph, { source: nodeA!, target: nodeC!, cost: (edge) => edge, heuristic })
        expect(Option.isSome(result)).toBe(true)