Typing PEPs

Introduction

This is the index of all Python Enhancement Proposals (PEPs) labelled under the ‘Typing’ topic. This is a sub-index of PEP 0, the PEP index.

Many recent PEPs propose changes to Python’s static type system or otherwise relate to type annotations. They are listed here for reference.

Index by Category

Other Informational PEPs

	PEP	Title	Authors
IF	482	Literature Overview for Type Hints	Langa
IF	483	The Theory of Type Hints	GvR, Levkivskyi

Accepted PEPs (accepted; may not be implemented yet)

	PEP	Title	Authors
SA	544	Protocols: Structural subtyping (static duck typing)	Levkivskyi, Lehtosalo, Langa
SA	563	Postponed Evaluation of Annotations	Langa
SA	586	Literal Types	Lee, Levkivskyi, Lehtosalo
SA	589	TypedDict: Type Hints for Dictionaries with a Fixed Set of Keys	Lehtosalo
SA	591	Adding a final qualifier to typing	Sullivan, Levkivskyi
SA	593	Flexible function and variable annotations	Varoquaux, Kashin
SA	604	Allow writing union types as X \| Y	PRADOS, Moss
SA	612	Parameter Specification Variables	Mendoza
SA	613	Explicit Type Aliases	Zhu
SA	646	Variadic Generics	Mendoza, Rahtz, Srinivasan, Siles
SA	647	User-Defined Type Guards	Traut
SA	655	Marking individual TypedDict items as required or potentially-missing	Foster
SA	673	Self Type	Srinivasan, Hilton-Balfe
SA	675	Arbitrary Literal String Type	Srinivasan, Bleaney
SA	681	Data Class Transforms	De Bonte, Traut
SA	688	Making the buffer protocol accessible in Python	Zijlstra
SA	692	Using TypedDict for more precise **kwargs typing	Magiera
SA	698	Override Decorator for Static Typing	Troxler, Xu, Zhu

Open PEPs (under consideration)

	PEP	Title	Authors
S	649	Deferred Evaluation Of Annotations Using Descriptors	Hastings
S	695	Type Parameter Syntax	Traut
S	696	Type defaults for TypeVarLikes	Hilton-Balfe
S	702	Marking deprecations using the type system	Zijlstra
S	705	TypedMapping: Type Hints for Mappings with a Fixed Set of Keys	Purcell

Finished PEPs (done, with a stable interface)

	PEP	Title	Authors
SF	484	Type Hints	GvR, Lehtosalo, Langa
SF	526	Syntax for Variable Annotations	Gonzalez, House, Levkivskyi, Roach, GvR
SF	561	Distributing and Packaging Type Information	Smith
SF	585	Type Hinting Generics In Standard Collections	Langa

Abandoned, Withdrawn, and Rejected PEPs

	PEP	Title	Authors
SR	677	Callable Type Syntax	Troxler, Srinivasan

Numerical Index

	PEP	Title	Authors
IF	482	Literature Overview for Type Hints	Langa
IF	483	The Theory of Type Hints	GvR, Levkivskyi
SF	484	Type Hints	GvR, Lehtosalo, Langa
SF	526	Syntax for Variable Annotations	Gonzalez, House, Levkivskyi, Roach, GvR
SA	544	Protocols: Structural subtyping (static duck typing)	Levkivskyi, Lehtosalo, Langa
SF	561	Distributing and Packaging Type Information	Smith
SA	563	Postponed Evaluation of Annotations	Langa
SF	585	Type Hinting Generics In Standard Collections	Langa
SA	586	Literal Types	Lee, Levkivskyi, Lehtosalo
SA	589	TypedDict: Type Hints for Dictionaries with a Fixed Set of Keys	Lehtosalo
SA	591	Adding a final qualifier to typing	Sullivan, Levkivskyi
SA	593	Flexible function and variable annotations	Varoquaux, Kashin
SA	604	Allow writing union types as X \| Y	PRADOS, Moss
SA	612	Parameter Specification Variables	Mendoza
SA	613	Explicit Type Aliases	Zhu
SA	646	Variadic Generics	Mendoza, Rahtz, Srinivasan, Siles
SA	647	User-Defined Type Guards	Traut
S	649	Deferred Evaluation Of Annotations Using Descriptors	Hastings
SA	655	Marking individual TypedDict items as required or potentially-missing	Foster
SA	673	Self Type	Srinivasan, Hilton-Balfe
SA	675	Arbitrary Literal String Type	Srinivasan, Bleaney
SR	677	Callable Type Syntax	Troxler, Srinivasan
SA	681	Data Class Transforms	De Bonte, Traut
SA	688	Making the buffer protocol accessible in Python	Zijlstra
SA	692	Using TypedDict for more precise **kwargs typing	Magiera
S	695	Type Parameter Syntax	Traut
S	696	Type defaults for TypeVarLikes	Hilton-Balfe
SA	698	Override Decorator for Static Typing	Troxler, Xu, Zhu
S	702	Marking deprecations using the type system	Zijlstra
S	705	TypedMapping: Type Hints for Mappings with a Fixed Set of Keys	Purcell

PEP Types Key

I — Informational: Non-normative PEP containing background, guidelines or other information relevant to the Python ecosystem
P — Process: Normative PEP describing or proposing a change to a Python community process, workflow or governance
S — Standards Track: Normative PEP with a new feature for Python, implementation change for CPython or interoperability standard for the ecosystem

More info in PEP 1.

PEP Status Key

A — Accepted: Normative proposal accepted for implementation
A — Active: Currently valid informational guidance, or an in-use process
D — Deferred: Inactive draft that may be taken up again at a later time
<No letter> — Draft: Proposal under active discussion and revision
F — Final: Accepted and implementation complete, or no longer active
P — Provisional: Provisionally accepted but additional feedback needed
R — Rejected: Formally declined and will not be accepted
S — Superseded: Replaced by another succeeding PEP
W — Withdrawn: Removed from consideration by sponsor or authors

More info in PEP 1.