refactor objects

internal/object/module.go

@@ -25,12 +25,12 @@ func (m Module) Inspect() string {
 }
 
 func (m Module) Get(index Object) (Object, error) {
-	key, ok := index.(Hashable)
+	key, ok := index.(Hasher)
 	if !ok {
 		return nil, fmt.Errorf("invalid module attribute %s", index.Type())
 	}
 
-	attr, found := m.Attrs.(*Hash).Pairs[key.HashKey()]
+	attr, found := m.Attrs.(*Hash).Pairs[key.Hash()]
 	if !found {
 		return Null{}, nil
 	}