diff --git a/libdino/src/util/weak_map.vala b/libdino/src/util/weak_map.vala
index 5a89be11..0fd9d55d 100644
--- a/libdino/src/util/weak_map.vala
+++ b/libdino/src/util/weak_map.vala
@@ -5,13 +5,30 @@ public class WeakMap<K, V> : Gee.AbstractMap<K, V> {
     private HashMap<K, weak V> hash_map;
     private HashMap<K, WeakNotifyWrapper> notify_map;
 
+    public HashDataFunc<K>? key_hash_func = null;
+    public EqualDataFunc<K>? key_equal_func = null;
+    public EqualDataFunc<V>? value_equal_func = null;
+
     public WeakMap(owned HashDataFunc<K>? key_hash_func = null, owned EqualDataFunc<K>? key_equal_func = null, owned EqualDataFunc<V>? value_equal_func = null) {
         if (!typeof(V).is_object()) {
             error("WeakMap only takes values that are Objects");
         }
 
-        hash_map = new HashMap<K, weak V>(key_hash_func, key_equal_func, value_equal_func);
-        notify_map = new HashMap<K, WeakNotifyWrapper>(key_hash_func, key_equal_func, value_equal_func);
+        this.key_hash_func = (owned)key_hash_func;
+        this.key_equal_func = (owned)key_equal_func;
+        this.value_equal_func = (owned)value_equal_func;
+
+        if (this.key_equal_func == null || this.key_equal_func == null || this.value_equal_func == null) {
+            hash_map = new HashMap<K, weak V>();
+            notify_map = new HashMap<K, WeakNotifyWrapper>();
+        } else {
+            hash_map = new HashMap<K, weak V>((v) => { return this.key_hash_func(v); },
+                    (a, b) => { return this.key_equal_func(a, b); },
+                    (a, b) => { return this.value_equal_func(a, b); });
+            notify_map = new HashMap<K, WeakNotifyWrapper>((v) => { return this.key_hash_func(v); },
+                    (a, b) => { return this.key_equal_func(a, b); },
+                    (a, b) => { return this.value_equal_func(a, b); });
+        }
     }
 
     public override void clear() {
@@ -60,25 +77,18 @@ public class WeakMap<K, V> : Gee.AbstractMap<K, V> {
     }
 
     public override bool unset(K key, out V value = null) {
-        if (!hash_map.has_key(key)) return false;
+        if (!hash_map.has_key(key)) {
+            value = null;
+            return false;
+        }
 
         Object v_obj = (Object) hash_map[key];
         v_obj.weak_unref(notify_map[key].func);
         notify_map.unset(key);
-        return hash_map.unset(key);
+        return hash_map.unset(key, out value);
     }
     public override Gee.Set<Gee.Map.Entry<K,V>> entries { owned get; }
 
-    [CCode (notify = false)]
-    public Gee.EqualDataFunc<K> key_equal_func {
-        get { return hash_map.key_equal_func; }
-    }
-
-    [CCode (notify = false)]
-    public Gee.HashDataFunc<K> key_hash_func {
-        get { return hash_map.key_hash_func; }
-    }
-
     public override Gee.Set<K> keys {
         owned get { return hash_map.keys; }
     }
@@ -87,11 +97,6 @@ public class WeakMap<K, V> : Gee.AbstractMap<K, V> {
 
     public override int size { get { return hash_map.size; } }
 
-    [CCode (notify = false)]
-    public Gee.EqualDataFunc<V> value_equal_func {
-        get { return hash_map.value_equal_func; }
-    }
-
     public override Gee.Collection<V> values {
         owned get {
             assert_not_reached();