1 files changed, 69 insertions, 0 deletions
diff --git a/asciidoc/collections.py b/asciidoc/collections.py
new file mode 100644
index 0000000..36cfded
--- /dev/null
+++ b/asciidoc/collections.py
@@ -0,0 +1,69 @@
+class AttrDict(dict):
+    """
+    Like a dictionary except values can be accessed as attributes i.e. obj.foo
+    can be used in addition to obj['foo'].
+    If an item is not present None is returned.
+    """
+    def __getattr__(self, key):
+        try:
+            return self[key]
+        except KeyError:
+            return None
+
+    def __setattr__(self, key, value):
+        self[key] = value
+
+    def __delattr__(self, key):
+        try:
+            del self[key]
+        except KeyError as k:
+            raise AttributeError(k)
+
+    def __repr__(self):
+        return '<AttrDict ' + dict.__repr__(self) + '>'
+
+    def __getstate__(self):
+        return dict(self)
+
+    def __setstate__(self, value):
+        for k, v in value.items():
+            self[k] = v
+
+
+class DefaultAttrDict(AttrDict):
+    def __getattr__(self, key):
+        try:
+            return self[key]
+        except KeyError as k:
+            if '_default' in self:
+                return self['_default']
+            else:
+                raise AttributeError from k
+
+
+class InsensitiveDict(dict):
+    """
+    Like a dictionary except key access is case insensitive.
+    Keys are stored in lower case.
+    """
+    def __getitem__(self, key):
+        return dict.__getitem__(self, key.lower())
+
+    def __setitem__(self, key, value):
+        dict.__setitem__(self, key.lower(), value)
+
+    def __delitem__(self, key):
+        dict.__delitem__(self, key.lower())
+
+    def get(self, key, default=None):
+        return dict.get(self, key.lower(), default)
+
+    def update(self, dict):
+        for k, v in dict.items():
+            self[k] = v
+
+    def setdefault(self, key, default=None):
+        return dict.setdefault(self, key.lower(), default)
+
+    def __contains__(self, key):
+        return key.lower() in dict(self)