---
id: orderly-set
version: "5.5.0"
license: unclear
license_treatment: permissive
maintenance: aging
---

# orderly-set — Orderly set

License: permissive · Maintenance: aging · Popularity: top 1,000 on PyPI

## Install

pip install orderly-set
uv add orderly-set
poetry add orderly-set

## Description

# Orderly Set 5.5.0

Orderly Set is a package containing multiple implementations of Ordered Set.


## OrderlySet

This implementation keeps the order in all set operations except set difference operations.
As a result, it can do set difference operations much faster than other implementations. Still 2X slower than of Python's built-in set.


## StableSet

A StableSet is a mutable set that remembers its insertion order.
Featuring: Fast O(1) insertion, deletion, iteration and membership testing.
But slow O(N) Index Lookup.

## StableSetEq

Same as StableSet but the order of items doesn't matter for equality comparisons.

## OrderedSet

An OrderedSet is a mutable data structure that is a hybrid of a list and a set.
It remembers its insertion order so that every entry has an index that can be looked up. 
Featuring: O(1) Index lookup, insertion, iteration and membership testing.
But slow O(N) Deletion.


## SortedSet

SortedSet is basically set but when printed, turned into string, or iterated over, returns the items in alphabetical order.

# Installation

`pip install orderly-set`

# Usage examples

An OrderedSet is created and used like a set:

    >>> from orderly_set import...

## AI interpretation — verify before relying

Orderly Set provides multiple ordered set implementations—OrderedSet, StableSet, OrderlySet, and SortedSet—each optimizing different trade-offs between insertion order preservation, index lookup speed, and set operation performance.

Verdict: Orderly Set is a stable, dependency-free library offering multiple ordered set variants with different performance profiles. It carries no known vulnerabilities and permissive licensing, but the aging maintenance status (399 days since last release) and small repository footprint (4 stars) suggest limited active development—suitable for projects needing specific ordered-set trade-offs but not for those requiring frequent updates.

[View on SkillFed](https://skillfed.io/packages/orderly-set) · [View on PyPI](https://pypi.org/project/orderly-set/)