Iteration Order Reliability

Discussions center on whether the order of elements in data structures like sets, dictionaries, or directories is guaranteed, meaningful, or safe to rely on, and the implications for code that assumes specific ordering.

➡️ Stable 0.6x Programming Languages
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Keywords

PriorityItems e.g PriorityItem CSS OP P2 ycombinator.com OK P1 OCD order ordering dictionary sorted ordered dir annotations matters procedure values

Sample Comments

kzrdude • Sep 9, 2016 • View on HN

They should say "arbitrary order"

LinAGKar • Jan 26, 2022 • View on HN

That doesn't explain the order

pvg • Feb 7, 2017 • View on HN

You might have better luck with this on SO but there's no guaranteed order (nor would it make much sense for there to be one)

zhng • Jun 14, 2014 • View on HN

It should as order is important.

mrwnmonm • Jul 16, 2013 • View on HN

why did you choose that order, is there a reason for it?

evmar • Jun 3, 2021 • View on HN

If the order matters, it's only as hard as using a (different) data structure that preserves order.

nl • Oct 8, 2020 • View on HN

That's not obvious in the order. Do you have somewhere we can read that?

boesboes • Apr 20, 2024 • View on HN

This seems related: https://news.ycombinator.com/item?id=39672111As in, order matters

impostervt • Jan 6, 2015 • View on HN

The order doesn't convey any meaning.

randallsquared • Jan 4, 2009 • View on HN

No, you've reintroduced ordering.