[cps] [refactoring] merge branch and edgeApply into sprout -- s…

…prout a node

TODO.md

@@ -1,4 +1,9 @@
-[cps] [space] [subway] `createSubwaySpace` -- fix `branch` and `edgeApply`
+[cps] [refactoring] rename `ramify` to `branch` -- branch a path
+
+[cps] [space] [subway] `createSubwaySpace`
+
+- `branch` -- 找到一站相邻的点
+- `edgeApply` -- 平凡的根据 edge 找到下一个节点
 
 [cps] [space] add debug options
 

src/problems/subway/SubwaySpace.ts

@@ -1,4 +1,4 @@
-import { type Space } from "../../solvers/cps"
+import { type Space } from "../../solvers/cps/index.js"
 import { type LineId, type StationId } from "./Subway.js"
 
 export type TakeLine = {
@@ -14,11 +14,8 @@ export function createSubwaySpace(initialStationId: StationId): SubwaySpace {
     name: "SubwaySpace",
     nodeIsEnd: (stationId) => stationId === initialStationId,
     nodeEqual: (left, right) => left === right,
-    branch: (stationId) => {
-      throw new Error("TODO")
-    },
-    edgeApply: (takeLine, stationId) => {
-      throw new Error("TODO")
+    sprout: () => {
+      throw new Error()
     },
   }
 }

src/solvers/cps/Path.ts

@@ -48,9 +48,8 @@ export function pathHasLoop<Edge, Node>(path: Path<Edge, Node>): boolean {
 export function ramify<Edge, Node>(
   path: Path<Node, Edge>,
 ): Array<Path<Node, Edge>> {
-  const edges = path.space.branch(path.current)
-  const newPaths = edges.map((edge) =>
-    extendPath(path, edge, path.space.edgeApply(edge, path.current)),
+    const newPaths = path.space.sprout(path.current).map(([edge, node]) =>
+    extendPath(path, edge, node),
   )
   return newPaths.filter((newPath) => !pathHasLoop(newPath))
 }

src/solvers/cps/Space.ts

@@ -2,6 +2,5 @@ export type Space<Node, Edge> = {
   name: string
   nodeIsEnd: (node: Node) => boolean
   nodeEqual: (left: Node, right: Node) => boolean
-  branch: (node: Node) => Array<Edge>
-  edgeApply: (edge: Edge, node: Node) => Node
+  sprout: (node: Node) => Array<[Edge, Node]>
 }