feat: implement recognizer

modules/@angular/router/src/url_tree.ts

@@ -1,4 +1,5 @@
 import { Tree, TreeNode } from './tree';
+import { shallowEqual } from './util';
 
 export class UrlTree extends Tree<UrlSegment> {
   constructor(root: TreeNode<UrlSegment>, public queryParameters: {[key: string]: string}, public fragment: string | null) {
@@ -7,5 +8,25 @@ export class UrlTree extends Tree<UrlSegment> {
 }
 
 export class UrlSegment {
-  constructor(public segment: any, public parameters: {[key: string]: string}) {}
-}
+  constructor(public path: string, public parameters: {[key: string]: string}) {}
+
+  toString() {
+    let params = [];
+    for (let prop in this.parameters) {
+      if (this.parameters.hasOwnProperty(prop)) {
+        params.push(`${prop}=${this.parameters[prop]}`);
+      }
+    }
+    const paramsString = params.length > 0 ? `(${params.join(',')})` : '';
+    return `${this.path}${paramsString}`;
+  }
+}
+
+export function equalUrlSegments(a: UrlSegment[], b: UrlSegment[]): boolean {
+  if (a.length !== b.length) return false;
+  for (let i = 0; i < a.length; ++i) {
+    if (a[i].path !== b[i].path) return false;
+    if (!shallowEqual(a[i].parameters, b[i].parameters)) return false;
+  }
+  return true;
+}