Allow non-string keys in hash tables

Author: felipernb

data_structures/hash_table.js

@@ -43,6 +43,7 @@ function HashTable(initialCapacity) {
  * (The hash value of the empty string is zero.)
  */
 HashTable.prototype.hash = function (s) {
+  if (typeof s !== 'string') s = JSON.stringify(s);
   var hash = 0;
   for (var i = 0; i < s.length; i++) {
     hash = ((hash << 5) - hash) + s.charCodeAt(i);

test/data_structures/hash_table.js

@@ -129,5 +129,15 @@ describe('Hash Table', function () {
     h.del('foo');
     assert.equal(h.get('foo'), undefined);
   });
+
+  it('should allow non-string keys', function () {
+    var h = new HashTable();
+    h.put(10, 5);
+    assert.equal(h.get(10), 5);
+
+    var o = {a: 'foo', b: 'bar'};
+    h.put(o, 'foo');
+    assert.equal(h.get(o), 'foo');
+  });
 });