# Copyright (c) 2003, Taro Ogawa.  All Rights Reserved.
# Copyright (c) 2013, Savoir-faire Linux inc.  All Rights Reserved.

# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
# This library 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
# Lesser General Public License for more details.
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
# MA 02110-1301 USA

class OrderedMapping(dict):
    def __init__(self, *pairs):
        self.order = []
        for key, val in pairs:
            self[key] = val
            
    def __setitem__(self, key, val):
        if key not in self:
            self.order.append(key)
        super(OrderedMapping, self).__setitem__(key, val)

    def __iter__(self):
        for item in self.order:
            yield item

    def __repr__(self):
        out = ["%s: %s"%(repr(item), repr(self[item])) for item in self]
        out = ", ".join(out)
        return "{%s}"%out