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This is the page for my SortedDict project. It's like a Python dictionary, but it keeps key/value pairs stored in key-sorted order. You can use any object that can do comparisons (responds to cmp(x, y)) as a key.


  • In-order traversal of keys
  • Ability to key things by unhashable values (lists, dicts, etc)
  • Acts like a dict


  • Assumes you know what you're doing: if your key is mutable and you change it, it can get lost
  • Undefined behavior if any comparison fails/does not behave consistently
  • Can perform up to 15% worse than Python dicts in worst-case random read/write cases
  • Not as tested/stable as Python dicts

Getting Started

First, install it:

python install

Then, use it:

import ordereddict
import random
od = ordereddict.OrderedDict()

y = range(100) + [str(x) for x in xrange(100)]

for i, x in enumerate(y):
    od[x] = "Entry #%i"%i

for key in y[:25]:
    del od[key]

for item in sorted(y):
    print "od[%r] = %r" % (item, od.get(item, "NOT FOUND??"))

print ", ".join(repr(key) for key in od)
print ", ".join(repr(value) for value in od.values())
print ", ".join(repr(item) for item in od.items())

print "100 in od?", 100 in od