GLEP: 1 Title: GLEP Purpose and Guidelines Version: $Revision: 1.1 $ Last-Modified: $Date: 2003/05/31 15:18:03 $ Author: Grant Goodyear Status: Draft Type: Informational Content-Type: text/x-rst Created: 31 May 2003 Post-History: What is a GLEP? ============== GLEP stands for "Gentoo Linux Enhancement Proposal". A GLEP is a design document providing information to the Gentoo Linux community, or describing a new feature for Gentoo Linux. (The GLEP concept, and, in fact, much of the text of this document, is liberally stolen from Python's `PEP-0001`_.) The GLEP should provide a concise technical specification of the feature and rationale for the feature. We intend GLEPs to be the primary mechanisms for proposing new features, for collecting community input on an issue, and for documenting the design decisions that have gone into Python. The GLEP author is responsible for building consensus within the community and documenting dissenting opinions. Because the GLEPs are maintained as text files under CVS control, their revision history is the historical record of the feature proposal [1]_. Kinds of GLEPs ============= There are two kinds of GLEPs. A Standards Track GLEP describes a new feature or implementation for Python. An Informational GLEP describes a Python design issue, or provides general guidelines or information to the Python community, but does not propose a new feature. Informational GLEPs do not necessarily represent a Python community consensus or recommendation, so users and implementors are free to ignore Informational GLEPs or follow their advice. GLEP Work Flow ============= The GLEP editors assign GLEP numbers and change their status. The current GLEP editors are David Goodger and Barry Warsaw. Please send all GLEP-related email to . The GLEP process begins with a new idea for Python. It is highly recommended that a single GLEP contain a single key proposal or new idea. The more focussed the GLEP, the more successful it tends to be. The GLEP editor reserves the right to reject GLEP proposals if they appear too unfocussed or too broad. If in doubt, split your GLEP into several well-focussed ones. Each GLEP must have a champion -- someone who writes the GLEP using the style and format described below, shepherds the discussions in the appropriate forums, and attempts to build community consensus around the idea. The GLEP champion (a.k.a. Author) should first attempt to ascertain whether the idea is GLEP-able. Small enhancements or patches often don't need a GLEP and can be injected into the Python development work flow with a patch submission to the SourceForge `patch manager`_ or `feature request tracker`_. The GLEP champion then emails the GLEP editor with a proposed title and a rough, but fleshed out, draft of the GLEP. This draft must be written in GLEP style as described below. If the GLEP editor approves, he will assign the GLEP a number, label it as Standards Track or Informational, give it status "Draft", and create and check-in the initial draft of the GLEP. The GLEP editor will not unreasonably deny a GLEP. Reasons for denying GLEP status include duplication of effort, being technically unsound, not providing proper motivation or addressing backwards compatibility, or not in keeping with the Python philosophy. The BDFL (Benevolent Dictator for Life, Guido van Rossum) can be consulted during the approval phase, and is the final arbitrator of the draft's GLEP-ability. If a pre-GLEP is rejected, the author may elect to take the pre-GLEP to the comp.lang.python newsgroup (a.k.a. python-list@python.org mailing list) to help flesh it out, gain feedback and consensus from the community at large, and improve the GLEP for re-submission. The author of the GLEP is then responsible for posting the GLEP to the community forums, and marshaling community support for it. As updates are necessary, the GLEP author can check in new versions if they have CVS commit permissions, or can email new GLEP versions to the GLEP editor for committing. Standards Track GLEPs consists of two parts, a design document and a reference implementation. The GLEP should be reviewed and accepted before a reference implementation is begun, unless a reference implementation will aid people in studying the GLEP. Standards Track GLEPs must include an implementation -- in the form of code, patch, or URL to same -- before it can be considered Final. GLEP authors are responsible for collecting community feedback on a GLEP before submitting it for review. A GLEP that has not been discussed on python-list@python.org and/or python-dev@python.org will not be accepted. However, wherever possible, long open-ended discussions on public mailing lists should be avoided. Strategies to keep the discussions efficient include, setting up a separate SIG mailing list for the topic, having the GLEP author accept private comments in the early design phases, etc. GLEP authors should use their discretion here. Once the authors have completed a GLEP, they must inform the GLEP editor that it is ready for review. GLEPs are reviewed by the BDFL and his chosen consultants, who may accept or reject a GLEP or send it back to the author(s) for revision. For a GLEP that is pre-determined to be acceptable (e.g., it is an obvious win as-is and/or its implementation has already been checked in) the BDFL may also initiate a GLEP review, first notifying the GLEP author(s) and giving them a chance to make revisions. For a GLEP to be accepted it must meet certain minimum criteria. It must be a clear and complete description of the proposed enhancement. The enhancement must represent a net improvement. The proposed implementation, if applicable, must be solid and must not complicate the interpreter unduly. Finally, a proposed enhancement must be "pythonic" in order to be accepted by the BDFL. (However, "pythonic" is an imprecise term; it may be defined as whatever is acceptable to the BDFL. This logic is intentionally circular.) See GLEP 2 [2]_ for standard library module acceptance criteria. Once a GLEP has been accepted, the reference implementation must be completed. When the reference implementation is complete and accepted by the BDFL, the status will be changed to "Final". A GLEP can also be assigned status "Deferred". The GLEP author or editor can assign the GLEP this status when no progress is being made on the GLEP. Once a GLEP is deferred, the GLEP editor can re-assign it to draft status. A GLEP can also be "Rejected". Perhaps after all is said and done it was not a good idea. It is still important to have a record of this fact. GLEPs can also be replaced by a different GLEP, rendering the original obsolete. This is intended for Informational GLEPs, where version 2 of an API can replace version 1. GLEP work flow is as follows:: Draft -> Accepted -> Final -> Replaced ^ +----> Rejected v Deferred Some Informational GLEPs may also have a status of "Active" if they are never meant to be completed. E.g. GLEP 1 (this GLEP). What belongs in a successful GLEP? ================================= Each GLEP should have the following parts: 1. Preamble -- RFC 822 style headers containing meta-data about the GLEP, including the GLEP number, a short descriptive title (limited to a maximum of 44 characters), the names, and optionally the contact info for each author, etc. 2. Abstract -- a short (~200 word) description of the technical issue being addressed. 3. Copyright/public domain -- Each GLEP must either be explicitly labelled as placed in the public domain (see this GLEP as an example) or licensed under the `Open Publication License`_. 4. Specification -- The technical specification should describe the syntax and semantics of any new language feature. The specification should be detailed enough to allow competing, interoperable implementations for any of the current Python platforms (CPython, Jython, Python .NET). 5. Motivation -- The motivation is critical for GLEPs that want to change the Python language. It should clearly explain why the existing language specification is inadequate to address the problem that the GLEP solves. GLEP submissions without sufficient motivation may be rejected outright. 6. Rationale -- The rationale fleshes out the specification by describing what motivated the design and why particular design decisions were made. It should describe alternate designs that were considered and related work, e.g. how the feature is supported in other languages. The rationale should provide evidence of consensus within the community and discuss important objections or concerns raised during discussion. 7. Backwards Compatibility -- All GLEPs that introduce backwards incompatibilities must include a section describing these incompatibilities and their severity. The GLEP must explain how the author proposes to deal with these incompatibilities. GLEP submissions without a sufficient backwards compatibility treatise may be rejected outright. 8. Reference Implementation -- The reference implementation must be completed before any GLEP is given status "Final", but it need not be completed before the GLEP is accepted. It is better to finish the specification and rationale first and reach consensus on it before writing code. The final implementation must include test code and documentation appropriate for either the Python language reference or the standard library reference. GLEP Formats and Templates ========================= There are two GLEP formats available to authors: plaintext and reStructuredText_. Plaintext GLEPs are written in plain ASCII text, contain minimal structural markup, and should adhere to a rigid style. GLEP 9 contains a boilerplate template [3]_ you can use to get started writing your plaintext GLEP. ReStructuredText_ GLEPs allow for rich markup that is still quite easy to read, but results in much better-looking and more functional HTML. GLEP 12 contains a boilerplate template [4]_ for use with reStructuredText GLEPs. There is a Python script that converts both styles of GLEPs to HTML for viewing on the web [5]_. Parsing and conversion of plaintext GLEPs is self-contained within the script. reStructuredText GLEPs are parsed and converted by Docutils_ code called from the script. GLEP Header Preamble =================== Each GLEP must begin with an RFC 822 style header preamble. The headers must appear in the following order. Headers marked with "*" are optional and are described below. All other headers are required. :: GLEP: Title: Version: Last-Modified: Author: * Discussions-To: Status: Type: * Content-Type: * Requires: Created: * Python-Version: Post-History: * Replaces: * Replaced-By: The Author header lists the names, and optionally the email addresses of all the authors/owners of the GLEP. The format of the Author header value must be Random J. User if the email address is included, and just Random J. User if the address is not given. For historical reasons the format "address@dom.ain (Random J. User)" may appear in a GLEP, however new GLEPs must use the mandated format above, and it is acceptable to change to this format when GLEPs are updated. If there are multiple authors, each should be on a separate line following RFC 2822 continuation line conventions. Note that personal email addresses in GLEPs will be obscured as a defense against spam harvesters. While a GLEP is in private discussions (usually during the initial Draft phase), a Discussions-To header will indicate the mailing list or URL where the GLEP is being discussed. No Discussions-To header is necessary if the GLEP is being discussed privately with the author, or on the python-list or python-dev email mailing lists. Note that email addresses in the Discussions-To header will not be obscured. The Type header specifies the type of GLEP: Informational or Standards Track. The format of a GLEP is specified with a Content-Type header. The acceptable values are "text/plain" for plaintext GLEPs (see GLEP 9 [3]_) and "text/x-rst" for reStructuredText GLEPs (see GLEP 12 [4]_). Plaintext ("text/plain") is the default if no Content-Type header is present. The Created header records the date that the GLEP was assigned a number, while Post-History is used to record the dates of when new versions of the GLEP are posted to python-list and/or python-dev. Both headers should be in dd-mmm-yyyy format, e.g. 14-Aug-2001. Standards Track GLEPs must have a Python-Version header which indicates the version of Python that the feature will be released with. Informational GLEPs do not need a Python-Version header. GLEPs may have a Requires header, indicating the GLEP numbers that this GLEP depends on. GLEPs may also have a Replaced-By header indicating that a GLEP has been rendered obsolete by a later document; the value is the number of the GLEP that replaces the current document. The newer GLEP must have a Replaces header containing the number of the GLEP that it rendered obsolete. Reporting GLEP Bugs, or Submitting GLEP Updates ============================================= How you report a bug, or submit a GLEP update depends on several factors, such as the maturity of the GLEP, the preferences of the GLEP author, and the nature of your comments. For the early draft stages of the GLEP, it's probably best to send your comments and changes directly to the GLEP author. For more mature, or finished GLEPs you may want to submit corrections to the SourceForge `bug manager`_ or better yet, the SourceForge `patch manager`_ so that your changes don't get lost. If the GLEP author is a SF developer, assign the bug/patch to him, otherwise assign it to the GLEP editor. When in doubt about where to send your changes, please check first with the GLEP author and/or GLEP editor. GLEP authors who are also SF committers, can update the GLEPs themselves by using "cvs commit" to commit their changes. Remember to also push the formatted GLEP text out to the web by doing the following:: % python pep2html.py -i NUM where NUM is the number of the GLEP you want to push out. See :: % python pep2html.py --help for details. Transferring GLEP Ownership ========================== It occasionally becomes necessary to transfer ownership of GLEPs to a new champion. In general, we'd like to retain the original author as a co-author of the transferred GLEP, but that's really up to the original author. A good reason to transfer ownership is because the original author no longer has the time or interest in updating it or following through with the GLEP process, or has fallen off the face of the 'net (i.e. is unreachable or not responding to email). A bad reason to transfer ownership is because you don't agree with the direction of the GLEP. We try to build consensus around a GLEP, but if that's not possible, you can always submit a competing GLEP. If you are interested in assuming ownership of a GLEP, send a message asking to take over, addressed to both the original author and the GLEP editor . If the original author doesn't respond to email in a timely manner, the GLEP editor will make a unilateral decision (it's not like such decisions can't be reversed :). References and Footnotes ======================== .. _PEP-0001: http://www.python.org/peps/pep-0001.html .. [1] This historical record is available by the normal CVS commands for retrieving older revisions. For those without direct access to the CVS tree, you can browse the current and past GLEP revisions via the SourceForge web site at http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/python/python/nondist/peps/ .. [2] GLEP 2, Procedure for Adding New Modules, Faassen (http://www.python.org/peps/pep-0002.html) .. [3] GLEP 9, Sample Plaintext GLEP Template, Warsaw (http://www.python.org/peps/pep-0009.html) .. [4] GLEP 12, Sample reStructuredText GLEP Template, Goodger, Warsaw (http://www.python.org/peps/pep-0012.html) .. [5] The script referred to here is pep2html.py, which lives in the same directory in the CVS tree as the GLEPs themselves. Try ``pep2html.py --help`` for details. The URL for viewing GLEPs on the web is http://www.python.org/peps/. .. _patch manager: http://sourceforge.net/tracker/?group_id=5470&atid=305470 .. _feature request tracker: http://sourceforge.net/tracker/?atid=355470&group_id=5470&func=browse .. _Open Publication License: http://www.opencontent.org/openpub/ .. _reStructuredText: http://docutils.sourceforge.net/rst.html .. _Docutils: http://docutils.sourceforge.net/ .. _bug manager: http://sourceforge.net/tracker/?group_id=5470&atid=105470 Copyright ========= This document has been placed in the public domain.