implement equals for maps in javascript

1 files changed, 8 insertions, 0 deletions

diff --git a/src/persistent-hash-map.mjs b/src/persistent-hash-map.mjs
index c2a792c..1851258 100644
--- a/src/persistent-hash-map.mjs
+++ b/src/persistent-hash-map.mjs
@@ -588,6 +588,7 @@ function forEach(root, fn) {
 }
 /** Extra wrapper to keep track of map size */
 export class PMap {
+  static NOT_FOUND = Symbol();
   constructor(root, size) {
     this.root = root;
     this.size = size;
@@ -599,6 +600,13 @@ export class PMap {
     });
     return h;
   }
+  equals(o) {
+    let equal = true;
+    forEach(this, (v, k) => {
+      equal = equal && isEqual(v, getWithDefault(o, k, PMap.NOT_FOUND));
+    });
+    return equal;
+  }
 }
 export function create() {
   return new PMap(undefined, 0);