--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/collections.py	Sat Aug 25 17:59:48 2018 +0200
@@ -0,0 +1,149 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# Libervia: a Salut à Toi frontend
+# Copyright (C) 2014 Jérôme Poisson <goffi@goffi.org>
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+class OrderedDict(object):
+    """Naive implementation of OrderedDict which is compatible with pyjamas"""
+
+    def __init__(self, *args, **kwargs):
+        self.__internal_dict = {}
+        self.__keys = [] # this list keep the keys in order
+        if args:
+            if len(args)>1:
+                raise TypeError("OrderedDict expected at most 1 arguments, got {}".format(len(args)))
+            if isinstance(args[0], (dict, OrderedDict)):
+                for key, value in args[0].iteritems():
+                    self[key] = value
+            for key, value in args[0]:
+                self[key] = value
+
+    def __len__(self):
+        return len(self.__keys)
+
+    def __setitem__(self, key, value):
+        if key not in self.__keys:
+            self.__keys.append(key)
+        self.__internal_dict[key] = value
+
+    def __getitem__(self, key):
+        return self.__internal_dict[key]
+
+    def __delitem__(self, key):
+        del self.__internal_dict[key]
+        self.__keys.remove(key)
+
+    def __contains__(self, key):
+        return key in self.__keys
+
+    def clear(self):
+        self.__internal_dict.clear()
+        del self.__keys[:]
+
+    def copy(self):
+        return OrderedDict(self)
+
+    @classmethod
+    def fromkeys(cls, seq, value=None):
+        ret = OrderedDict()
+        for key in seq:
+            ret[key] = value
+        return ret
+
+    def get(self, key, default=None):
+        try:
+            return self.__internal_dict[key]
+        except KeyError:
+            return default
+
+    def has_key(self, key):
+        return key in self.__keys
+
+    def keys(self):
+        return self.__keys[:]
+
+    def iterkeys(self):
+        for key in self.__keys:
+            yield key
+
+    def items(self):
+        ret = []
+        for key in self.__keys:
+            ret.append((key, self.__internal_dict[key]))
+        return ret
+
+    def iteritems(self):
+        for key in self.__keys:
+            yield (key, self.__internal_dict[key])
+
+    def values(self):
+        ret = []
+        for key in self.__keys:
+            ret.append(self.__internal_dict[key])
+        return ret
+
+    def itervalues(self):
+        for key in self.__keys:
+            yield (self.__internal_dict[key])
+
+    def popitem(self, last=True):
+        try:
+            key = self.__keys.pop(-1 if last else 0)
+        except IndexError:
+            raise KeyError('dictionnary is empty')
+        value = self.__internal_dict.pop(key)
+        return((key, value))
+
+    def setdefault(self, key, default=None):
+        try:
+            return self.__internal_dict[key]
+        except KeyError:
+            self[key] = default
+            return default
+
+    def update(self, *args, **kwargs):
+        if len(args) > 1:
+            raise TypeError('udpate expected at most 1 argument, got {}'.format(len(args)))
+        if args:
+            if hasattr(args[0], 'keys'):
+                for k in args[0]:
+                    self[k] = args[0][k]
+            else:
+                for (k, v) in args[0]:
+                    self[k] = v
+        for k, v in kwargs.items():
+            self[k] = v
+
+    def pop(self, *args):
+        if not args:
+            raise TypeError('pop expected at least 1 argument, got 0')
+        try:
+            self.__internal_dict.pop(args[0])
+        except KeyError:
+            if len(args) == 2:
+                return args[1]
+            raise KeyError(args[0])
+        self.__keys.remove(args[0])
+
+    def viewitems(self):
+        raise NotImplementedError
+
+    def viewkeys(self):
+        raise NotImplementedError
+
+    def viewvalues(self):
+        raise NotImplementedError