Graph.nodes — API

Graph.nodesconsteffect/Graph.ts:4716

<N, E, T extends Kind = "directed">(
  graph: Graph<N, E, T> | MutableGraph<N, E, T>
): NodeWalker<N>

Creates an iterator over all node indices in the graph.

Details

The iterator produces node indices in the order they were added to the graph. This provides access to all nodes regardless of connectivity.

Example (Iterating all nodes)

import { Graph } from "effect"

const graph = Graph.directed<string, number>((mutable) => {
  const a = Graph.addNode(mutable, "A")
  const b = Graph.addNode(mutable, "B")
  const c = Graph.addNode(mutable, "C")
  Graph.addEdge(mutable, a, b, 1)
})

const indices = Array.from(Graph.indices(Graph.nodes(graph)))
console.log(indices) // [0, 1, 2]

iterators

Source effect/Graph.ts:471620 lines

export const nodes = <N, E, T extends Kind = "directed">(
  graph: Graph<N, E, T> | MutableGraph<N, E, T>
): NodeWalker<N> =>
  new Walker((f) => ({
    [Symbol.iterator]() {
      const nodeMap = graph.nodes
      const iterator = nodeMap.entries()

      return {
        next() {
          const result = iterator.next()
          if (result.done) {
            return { done: true, value: undefined }
          }
          const [nodeIndex, nodeData] = result.value
          return { done: false, value: f(nodeIndex, nodeData) }
        }
      }
    }
  }))