1 files changed, 71 insertions, 0 deletions
diff --git a/game/python-extra/utils/dicts/chained_dict.py b/game/python-extra/utils/dicts/chained_dict.py
new file mode 100644
index 0000000..f1fe36f
--- /dev/null
+++ b/game/python-extra/utils/dicts/chained_dict.py
@@ -0,0 +1,71 @@
+from collections import MutableMapping
+from itertools import chain
+
+
+class ChainedDict(MutableMapping):
+
+    def __init__(self, parent=None, **kwargs):
+        self.__parent = parent
+        self.__deleted_keys = set()
+        self.__data = kwargs
+
+    def __contains__(self, key):
+        if self.__parent is not None:
+            return (
+                (key in self.__data or key in self.__parent)
+                and key not in self.__deleted_keys
+            )
+        return key in self.__data
+
+    def __getitem__(self, key):
+        try:
+            return self.__data[key]
+        except KeyError:
+            if self.__parent is not None and key not in self.__deleted_keys:
+                return self.__parent[key]
+            else:
+                raise
+
+    def __setitem__(self, key, val):
+        self.__data[key] = val
+        self.__deleted_keys.discard(key)
+
+    def __delitem__(self, key):
+        if key in self:
+            self.__deleted_keys.add(key)
+            try:
+                del self.__data[key]
+            except KeyError:
+                pass
+        else:
+            raise KeyError(key)
+
+    def __repr__(self):
+        return "{}({})".format(self.__class__.__name__, dict(self.items()))
+
+    def __iter__(self):
+        return self.keys()
+
+    def __len__(self):
+        return len(list(self.keys()))
+
+    def iterkeys(self):
+        yielded = set(self.__deleted_keys)
+        if self.__parent is None:
+            iterable = self.__data.keys()
+        else:
+            iterable = chain(self.__parent.keys(), self.__data.keys())
+
+        for key in iterable:
+            if key in yielded:
+                continue
+            yield key
+            yielded.add(key)
+
+    keys = iterkeys
+
+    def iteritems(self):
+        for key in self.iterkeys():
+            yield key, self[key]
+
+    items = iteritems