Stop using the Hashable interface.

utils/pub/yaml/yaml_map.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * This class wraps behaves almost identically to the normal Dart Map
  * implementation, with the following differences:
  *
  * * It allows null, NaN, boolean, list, and map keys.
- * * It is itself Hashable.
  * * It defines `==` structurally. That is, `yamlMap1 == yamlMap2` if they have
  *   the same contents.
+ * * It has a compatible [hashCode] method.
  */
-class YamlMap implements Map, Hashable {
+class YamlMap implements Map {
   Map _map;
 
   YamlMap() : _map = new Map();
 
   YamlMap.from(Map map) : _map = new Map.from(map);
 
   YamlMap._wrap(this._map);
 
   bool containsValue(value) => _map.containsValue(value);
   bool containsKey(key) => _map.containsKey(_wrapKey(key));
@@ skipping 30 matching lines @@
   }
 
   /** Unwraps an object that was used as a key in the map. */
   _unwrapKey(obj) => obj is _WrappedHashKey ? obj.value : obj;
 }
 
 /**
  * A class for wrapping normally-unhashable objects that are being used as keys
  * in a YamlMap.
  */
-class _WrappedHashKey implements Hashable {
+class _WrappedHashKey  {

[Mads Ager (google), 2012/09/27 12:48:27]

hep

   var value;
 
   _WrappedHashKey(this.value);
 
   int hashCode() => _hashCode(value);
 
   String toString() => value.toString();
 
   /** This is defined as both values being structurally equal. */
   bool operator ==(other) {
@@ skipping 29 matching lines @@
       for (var e in obj) {
         hash ^= _hashCode(e, parents);
       }
       return hash;
     }
     return obj.hashCode();
   } finally {
     parents.removeLast();
   }
 }