fastenum

Based on python/cpython#17669 and python/cpython#16483

Patch for stdlib enum that makes it fast.

How fast?

• ~10x faster name/value access
• ~6x faster access to enum members
• ~2x faster values positive check
• ~3x faster values negative check
• ~3x faster iteration
• ~100x faster new Flags and IntFlags creation for Python 3.8 and below

Wow this is fast! How do I use it?

First, install it from PyPi using pip

pip install f-enum

or using poetry

poetry add f-enum

Then enable the patch just by calling fastenum.enable() once at the start of your programm:

import fastenum

fastenum.enable()

You don't need to re-apply patch across different modules: once it's enabled, it'll work everywhere.

What's changed?

fastenum is designed to give effortless boost for all enums from stdlib. That means that none of optimizations should break existing code, thus requiring no changes other than installing and activating the library.

Here are summary of internal changes:

• Optimized Enum.__new__
• Remove EnumMeta.__getattr__
• Store Enum.name and .value in members __dict__ for faster access
• Replace Enum._member_names_ with ._unique_member_map_ for faster lookups and iteration (old arg still remains)
• Replace _EmumMeta._member_names and ._last_values with .members mapping (old args still remain)
• Add support for direct setting and getting class attrs on DynamicClassAttribute without need to use slow __getattr__
• Various minor improvements