[padthai]

Why do you use OrderedDict for now that regular dicts are ordered by default?

[Flimm]

Two dictionaries with equal keys and values are considered equal in Python, even if the order of the entries differ. By contrast, two OrderedDict objects are only equal if their respective entries are equal and if their order does not differ.

[d0mine]

It may be more explicit: OrderedDict has move_to_end() which may be useful e.g., for implementing lru_cache-like functionality (like deque.rotate but with arbitrary keys).

[masklinn]

OTOH that’s a lot less useful now that functools.lru_cache exists: it’s more specialised so it’s lighter, more efficient, and thread-safe. So unless you have extended flexibility requirements around your LRU, OD loses a lot there.

And if you’re using a FIFO cache, threading a regular dict through a separate fifo (whether linked list or deque) is more efficient in my experience of implementing both S3 and Sieve.

[heavyset_go]

OrderedDicts have some convenience methods and features that ordinary dicts don't have.

[wodenokoto]

Do you have any examples?

[rbanffy]

Also, dicts can become unordered at any time in the future. Right now the OrderedDict implementation is a thin layer over dict, but there are no guarantees it’ll always be that.

[judicious]

I work with different versions of Python3 (and 2 unfortunately) and some code is still in 3.6, hence I used OrderedDicts.

[mixmastamyk]

3.6 was the first with the new ordered by default dicts, even though wasn't specc'd until 3.7.

[sgarland]

As someone who just had to backport a fairly large script to support 3.6, I found myself surprised at how much had changed. Dataclasses? Nope. `__future__.annotations`? Nope. `namedtuple.defaults`? Nope.

It's also been frustrating with the lack of tooling support. I mean, I get it – it's hideously EOL'd – but I can't use Poetry, uv, pytest... at least it still has type hints.