This PEP proposes a temporary moratorium (suspension) of all changesto the Python language syntax, semantics, and built-ins for a periodof at least two years from the release of Python 3.1. In particular, themoratorium would include Python 3.2 (to be released 18-24 months after3.1) but allow Python 3.3 (assuming it is not released prematurely) toonce again include language changes.
This suspension of features is designed to allow non-CPython implementationsto “catch up” to the core implementation of the language, help ease adoptionof Python 3.x, and provide a more stable base for the community.
This idea was proposed by Guido van Rossum on the python-ideas[1] mailinglist. The premise of his email was to slow the alteration of the Python coresyntax, builtins and semantics to allow non-CPython implementations to catchup to the current state of Python, both 2.x and 3.x.
Python, as a language is more than the core implementation –CPython – with a rich, mature and vibrant community of implementations, suchas Jython[2], IronPython[3] and PyPy[4] that are a benefit not only tothe community, but to the language itself.
Still others, such as Unladen Swallow[5] (a branch of CPython) seek not tocreate an alternative implementation, but rather they seek to enhance theperformance and implementation of CPython itself.
Python 3.x was a large part of the last several years of Python’sdevelopment. Its release, as well as a bevy of changes to the languageintroduced by it and the previous 2.6.x releases, puts alternativeimplementations at a severe disadvantage in “keeping pace” with core pythondevelopment.
Additionally, many of the changes put into the recent releases of the languageas implemented by CPython have not yet seen widespread usage by thegeneral user population. For example, most users are limited to the versionof the interpreter (typically CPython) which comes pre-installed with theiroperating system. Most OS vendors are just barely beginning to ship Python 2.6– even fewer are shipping Python 3.x.
As it is expected that Python 2.7 be the effective “end of life” of the Python2.x code line, with Python 3.x being the future, it is in the best interest ofPython core development to temporarily suspend the alteration of the languageitself to allow all of these external entities to catch up and to assist inthe adoption of, and migration to, Python 3.x
Finally, the moratorium is intended to free up cycles within core developmentto focus on other issues, such as the CPython interpreter and improvementstherein, the standard library, etc.
This moratorium does not allow for exceptions – once accepted, any pendingchanges to the syntax or semantics of the language will be postponed until themoratorium is lifted.
This moratorium does not attempt to apply to any other Python implementationmeaning that if desired other implementations may add features which deviatefrom the standard implementation.
It is important to note that the moratorium covers all changes since the releaseof Python 3.1. This rule is intended to avoid features being rushed or smuggledinto the CPython source tree while the moratorium is being discussed. A reviewof the NEWS file for the py3k development branch showed no commits would need tobe rolled back in order to meet this goal.
The time period of the moratorium can only be extended through a new PEP.
This document has been placed in the public domain.
Source:https://github.com/python/peps/blob/main/peps/pep-3003.rst
Last modified:2025-02-01 08:59:27 GMT