mongo-ruby-driver/lib/mongo/util/ordered_hash.rb

55 lines
1.3 KiB
Ruby

# --
# Copyright (C) 2008-2009 10gen Inc.
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU Affero General Public License, version 3, as
# published by the Free Software Foundation.
#
# 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/>.
# ++
# A hash in which the order of keys are preserved.
class OrderedHash < Hash
attr_accessor :ordered_keys
def keys
@ordered_keys || []
end
def []=(key, value)
@ordered_keys ||= []
@ordered_keys << key unless @ordered_keys.include?(key)
super(key, value)
end
def each
@ordered_keys ||= []
@ordered_keys.each { |k| yield k, self[k] }
end
def values
collect { |k, v| v }
end
def merge(other)
oh = self.dup
oh.merge!(other)
oh
end
def merge!(other)
@ordered_keys ||= []
@ordered_keys += other.keys # unordered if not an OrderedHash
@ordered_keys.uniq!
super(other)
end
end