forked from rust-lang/rfcs
-
Notifications
You must be signed in to change notification settings - Fork 1
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge pull request #1 from rust-lang/master
d
- Loading branch information
Showing
306 changed files
with
70,371 additions
and
560 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -1,29 +1,47 @@ | ||
- Feature Name: (fill me in with a unique ident, my_awesome_feature) | ||
- Start Date: (fill me in with today's date, YYYY-MM-DD) | ||
- RFC PR #: (leave this empty) | ||
- Rust Issue #: (leave this empty) | ||
- RFC PR: (leave this empty) | ||
- Rust Issue: (leave this empty) | ||
|
||
# Summary | ||
[summary]: #summary | ||
|
||
One para explanation of the feature. | ||
|
||
# Motivation | ||
[motivation]: #motivation | ||
|
||
Why are we doing this? What use cases does it support? What is the expected outcome? | ||
|
||
# Detailed design | ||
[design]: #detailed-design | ||
|
||
This is the bulk of the RFC. Explain the design in enough detail for somebody familiar | ||
with the language to understand, and for somebody familiar with the compiler to implement. | ||
This should get into specifics and corner-cases, and include examples of how the feature is used. | ||
|
||
# How We Teach This | ||
[how-we-teach-this]: #how-we-teach-this | ||
|
||
What names and terminology work best for these concepts and why? | ||
How is this idea best presented—as a continuation of existing Rust patterns, or as a wholly new one? | ||
|
||
Would the acceptance of this proposal change how Rust is taught to new users at any level? | ||
How should this feature be introduced and taught to existing Rust users? | ||
|
||
What additions or changes to the Rust Reference, _The Rust Programming Language_, and/or _Rust by Example_ does it entail? | ||
|
||
# Drawbacks | ||
[drawbacks]: #drawbacks | ||
|
||
Why should we *not* do this? | ||
|
||
# Alternatives | ||
[alternatives]: #alternatives | ||
|
||
What other designs have been considered? What is the impact of not doing this? | ||
|
||
# Unresolved questions | ||
[unresolved]: #unresolved-questions | ||
|
||
What parts of the design are still TBD? |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -1,78 +1,265 @@ | ||
# Rust RFCs | ||
[Rust RFCs]: #rust-rfcs | ||
|
||
Many changes, including bug fixes and documentation improvements can be | ||
Many changes, including bug fixes and documentation improvements can be | ||
implemented and reviewed via the normal GitHub pull request workflow. | ||
|
||
Some changes though are "substantial", and we ask that these be put | ||
through a bit of a design process and produce a consensus among the Rust | ||
community and the [core team]. | ||
Some changes though are "substantial", and we ask that these be put | ||
through a bit of a design process and produce a consensus among the Rust | ||
community and the [sub-team]s. | ||
|
||
The "RFC" (request for comments) process is intended to provide a | ||
consistent and controlled path for new features to enter the language | ||
and standard libraries, so that all stakeholders can be confident about | ||
consistent and controlled path for new features to enter the language | ||
and standard libraries, so that all stakeholders can be confident about | ||
the direction the language is evolving in. | ||
|
||
## Table of Contents | ||
[Table of Contents]: #table-of-contents | ||
* [Opening](#rust-rfcs) | ||
* [Table of Contents] | ||
* [When you need to follow this process] | ||
* [Before creating an RFC] | ||
* [What the process is] | ||
* [The role of the shepherd] | ||
* [The RFC life-cycle] | ||
* [Reviewing RFC's] | ||
* [Implementing an RFC] | ||
* [RFC Postponement] | ||
* [Help this is all too informal!] | ||
|
||
|
||
## When you need to follow this process | ||
[When you need to follow this process]: #when-you-need-to-follow-this-process | ||
|
||
You need to follow this process if you intend to make "substantial" | ||
changes to the Rust distribution. What constitutes a "substantial" | ||
change is evolving based on community norms, but may include the following. | ||
You need to follow this process if you intend to make "substantial" changes to | ||
Rust, Cargo, Crates.io, or the RFC process itself. What constitutes a | ||
"substantial" change is evolving based on community norms and varies depending | ||
on what part of the ecosystem you are proposing to change, but may include the | ||
following. | ||
|
||
- Any semantic or syntactic change to the language that is not a bugfix. | ||
- Changes to the interface between the compiler and libraries, | ||
including lang items and intrinsics. | ||
- Additions to `std` | ||
- Removing language features, including those that are feature-gated. | ||
- Changes to the interface between the compiler and libraries, including lang | ||
items and intrinsics. | ||
- Additions to `std`. | ||
|
||
Some changes do not require an RFC: | ||
|
||
- Rephrasing, reorganizing, refactoring, or otherwise "changing shape | ||
- Rephrasing, reorganizing, refactoring, or otherwise "changing shape | ||
does not change meaning". | ||
- Additions that strictly improve objective, numerical quality | ||
criteria (warning removal, speedup, better platform coverage, more | ||
- Additions that strictly improve objective, numerical quality | ||
criteria (warning removal, speedup, better platform coverage, more | ||
parallelism, trap more errors, etc.) | ||
- Additions only likely to be _noticed by_ other developers-of-rust, | ||
- Additions only likely to be _noticed by_ other developers-of-rust, | ||
invisible to users-of-rust. | ||
|
||
If you submit a pull request to implement a new feature without going | ||
through the RFC process, it may be closed with a polite request to | ||
If you submit a pull request to implement a new feature without going | ||
through the RFC process, it may be closed with a polite request to | ||
submit an RFC first. | ||
|
||
For more details on when an RFC is required, please see the following specific | ||
guidelines, these correspond with some of the Rust community's | ||
[sub-teams](http://www.rust-lang.org/team.html): | ||
|
||
* [language changes](lang_changes.md), | ||
* [library changes](libs_changes.md), | ||
* [compiler changes](compiler_changes.md). | ||
|
||
|
||
## Before creating an RFC | ||
[Before creating an RFC]: #before-creating-an-rfc | ||
|
||
A hastily-proposed RFC can hurt its chances of acceptance. Low quality | ||
proposals, proposals for previously-rejected features, or those that | ||
don't fit into the near-term roadmap, may be quickly rejected, which | ||
can be demotivating for the unprepared contributor. Laying some | ||
groundwork ahead of the RFC can make the process smoother. | ||
|
||
Although there is no single way to prepare for submitting an RFC, it | ||
is generally a good idea to pursue feedback from other project | ||
developers beforehand, to ascertain that the RFC may be desirable: | ||
having a consistent impact on the project requires concerted effort | ||
toward consensus-building. | ||
|
||
The most common preparations for writing and submitting an RFC include | ||
talking the idea over on #rust-internals, filing and discusssing ideas | ||
on the [RFC issue tracker][issues], and occasionally posting | ||
'pre-RFCs' on [the developer discussion forum][discuss] for early | ||
review. | ||
|
||
As a rule of thumb, receiving encouraging feedback from long-standing | ||
project developers, and particularly members of the relevant [sub-team] | ||
is a good indication that the RFC is worth pursuing. | ||
|
||
[issues]: https://github.com/rust-lang/rfcs/issues | ||
[discuss]: http://internals.rust-lang.org/ | ||
|
||
|
||
## What the process is | ||
[What the process is]: #what-the-process-is | ||
|
||
In short, to get a major feature added to Rust, one must first get the | ||
RFC merged into the RFC repo as a markdown file. At that point the RFC | ||
is 'active' and may be implemented with the goal of eventual inclusion | ||
In short, to get a major feature added to Rust, one must first get the | ||
RFC merged into the RFC repo as a markdown file. At that point the RFC | ||
is 'active' and may be implemented with the goal of eventual inclusion | ||
into Rust. | ||
|
||
* Fork the RFC repo http://github.com/rust-lang/rfcs | ||
* Copy `0000-template.md` to `active/0000-my-feature.md` (where | ||
'my-feature' is descriptive. don't assign an RFC number yet). | ||
* Fill in the RFC | ||
* Submit a pull request. The pull request is the time to get review of | ||
the design from the larger community. | ||
* Build consensus and integrate feedback. RFCs that have broad support | ||
are much more likely to make progress than those that don't receive any | ||
comments. | ||
* Eventually, somebody on the [core team] will either accept the RFC by | ||
merging the pull request and assigning the RFC a number, at which point | ||
the RFC is 'active', or reject it by closing the pull request. | ||
|
||
Once an RFC becomes active then authors may implement it and submit the | ||
feature as a pull request to the Rust repo. An 'active' is not a rubber | ||
stamp, and in particular still does not mean the feature will ultimately | ||
be merged; it does mean that in principle all the major stakeholders | ||
have agreed to the feature and are amenable to merging it. | ||
|
||
Modifications to active RFC's can be done in followup PR's. An RFC that | ||
makes it through the entire process to implementation is considered | ||
'complete' and is moved to the 'complete' folder; an RFC that fails | ||
after becoming active is 'inactive' and moves to the 'inactive' folder. | ||
* Copy `0000-template.md` to `text/0000-my-feature.md` (where 'my-feature' is | ||
descriptive. don't assign an RFC number yet). | ||
* Fill in the RFC. Put care into the details: RFCs that do not present | ||
convincing motivation, demonstrate understanding of the impact of the design, or | ||
are disingenuous about the drawbacks or alternatives tend to be poorly-received. | ||
* Submit a pull request. As a pull request the RFC will receive design feedback | ||
from the larger community, and the author should be prepared to revise it in | ||
response. | ||
* Each pull request will be labeled with the most relevant [sub-team]. | ||
* Each sub-team triages its RFC pull requests. The sub-team will either close | ||
the pull request (for RFCs that clearly will not be accepted) or assign it a | ||
*shepherd*. The shepherd is a trusted developer who is familiar with the RFC | ||
process, who will help to move the RFC forward, and ensure that the right people | ||
see and review it. | ||
* Build consensus and integrate feedback. RFCs that have broad support are much | ||
more likely to make progress than those that don't receive any comments. The | ||
shepherd assigned to your RFC should help you get feedback from Rust developers | ||
as well. | ||
* The shepherd may schedule meetings with the author and/or relevant | ||
stakeholders to discuss the issues in greater detail. | ||
* The sub-team will discuss the RFC pull request, as much as possible in the | ||
comment thread of the pull request itself. Offline discussion will be summarized | ||
on the pull request comment thread. | ||
* RFCs rarely go through this process unchanged, especially as alternatives and | ||
drawbacks are shown. You can make edits, big and small, to the RFC to | ||
clarify or change the design, but make changes as new commits to the pull | ||
request, and leave a comment on the pull request explaining your changes. | ||
Specifically, do not squash or rebase commits after they are visible on the pull | ||
request. | ||
* Once both proponents and opponents have clarified and defended positions and | ||
the conversation has settled, the RFC will enter its *final comment period* | ||
(FCP). This is a final opportunity for the community to comment on the pull | ||
request and is a reminder for all members of the sub-team to be aware of the | ||
RFC. | ||
* The FCP lasts one week. It may be extended if consensus between sub-team | ||
members cannot be reached. At the end of the FCP, the [sub-team] will either | ||
accept the RFC by merging the pull request, assigning the RFC a number | ||
(corresponding to the pull request number), at which point the RFC is 'active', | ||
or reject it by closing the pull request. How exactly the sub-team decide on an | ||
RFC is up to the sub-team. | ||
|
||
|
||
## The role of the shepherd | ||
[The role of the shepherd]: #the-role-of-the-shepherd | ||
|
||
During triage, every RFC will either be closed or assigned a shepherd from the | ||
relevant sub-team. The role of the shepherd is to move the RFC through the | ||
process. This starts with simply reading the RFC in detail and providing initial | ||
feedback. The shepherd should also solicit feedback from people who are likely | ||
to have strong opinions about the RFC. When this feedback has been incorporated | ||
and the RFC seems to be in a steady state, the shepherd and/or sub-team leader | ||
will announce an FCP. In general, the idea here is to "front-load" as much of | ||
the feedback as possible before the point where we actually reach a decision - | ||
by the end of the FCP, the decision on whether or not to accept the RFC should | ||
usually be obvious from the RFC discussion thread. On occasion, there may not be | ||
consensus but discussion has stalled. In this case, the relevant team will make | ||
a decision. | ||
|
||
|
||
## The RFC life-cycle | ||
[The RFC life-cycle]: #the-rfc-life-cycle | ||
|
||
Once an RFC becomes active then authors may implement it and submit | ||
the feature as a pull request to the Rust repo. Being 'active' is not | ||
a rubber stamp, and in particular still does not mean the feature will | ||
ultimately be merged; it does mean that in principle all the major | ||
stakeholders have agreed to the feature and are amenable to merging | ||
it. | ||
|
||
Furthermore, the fact that a given RFC has been accepted and is | ||
'active' implies nothing about what priority is assigned to its | ||
implementation, nor does it imply anything about whether a Rust | ||
developer has been assigned the task of implementing the feature. | ||
While it is not *necessary* that the author of the RFC also write the | ||
implementation, it is by far the most effective way to see an RFC | ||
through to completion: authors should not expect that other project | ||
developers will take on responsibility for implementing their accepted | ||
feature. | ||
|
||
Modifications to active RFC's can be done in follow-up pull requests. We strive | ||
to write each RFC in a manner that it will reflect the final design of | ||
the feature; but the nature of the process means that we cannot expect | ||
every merged RFC to actually reflect what the end result will be at | ||
the time of the next major release. | ||
|
||
In general, once accepted, RFCs should not be substantially changed. Only very | ||
minor changes should be submitted as amendments. More substantial changes should | ||
be new RFCs, with a note added to the original RFC. Exactly what counts as a | ||
"very minor change" is up to the sub-team to decide. There are some more | ||
specific guidelines in the sub-team RFC guidelines for the [language](lang_changes.md), | ||
[libraries](libs_changes.md), and [compiler](compiler_changes.md). | ||
|
||
|
||
## Reviewing RFC's | ||
[Reviewing RFC's]: #reviewing-rfcs | ||
|
||
While the RFC pull request is up, the shepherd may schedule meetings with the | ||
author and/or relevant stakeholders to discuss the issues in greater | ||
detail, and in some cases the topic may be discussed at a sub-team | ||
meeting. In either case a summary from the meeting will be | ||
posted back to the RFC pull request. | ||
|
||
A sub-team makes final decisions about RFCs after the benefits and drawbacks are | ||
well understood. These decisions can be made at any time, but the sub-team will | ||
regularly issue decisions. When a decision is made, the RFC pull request will | ||
either be merged or closed. In either case, if the reasoning is not clear from | ||
the discussion in thread, the sub-team will add a comment describing the | ||
rationale for the decision. | ||
|
||
|
||
## Implementing an RFC | ||
[Implementing an RFC]: #implementing-an-rfc | ||
|
||
Some accepted RFC's represent vital features that need to be | ||
implemented right away. Other accepted RFC's can represent features | ||
that can wait until some arbitrary developer feels like doing the | ||
work. Every accepted RFC has an associated issue tracking its | ||
implementation in the Rust repository; thus that associated issue can | ||
be assigned a priority via the triage process that the team uses for | ||
all issues in the Rust repository. | ||
|
||
The author of an RFC is not obligated to implement it. Of course, the | ||
RFC author (like any other developer) is welcome to post an | ||
implementation for review after the RFC has been accepted. | ||
|
||
If you are interested in working on the implementation for an 'active' | ||
RFC, but cannot determine if someone else is already working on it, | ||
feel free to ask (e.g. by leaving a comment on the associated issue). | ||
|
||
|
||
## RFC Postponement | ||
[RFC Postponement]: #rfc-postponement | ||
|
||
Some RFC pull requests are tagged with the 'postponed' label when they are | ||
closed (as part of the rejection process). An RFC closed with “postponed” is | ||
marked as such because we want neither to think about evaluating the proposal | ||
nor about implementing the described feature until some time in the future, and | ||
we believe that we can afford to wait until then to do so. Historically, | ||
"postponed" was used to postpone features until after 1.0. Postponed pull | ||
requests may be re-opened when the time is right. We don't have any formal | ||
process for that, you should ask members of the relevant sub-team. | ||
|
||
Usually an RFC pull request marked as “postponed” has already passed | ||
an informal first round of evaluation, namely the round of “do we | ||
think we would ever possibly consider making this change, as outlined | ||
in the RFC pull request, or some semi-obvious variation of it.” (When | ||
the answer to the latter question is “no”, then the appropriate | ||
response is to close the RFC, not postpone it.) | ||
|
||
|
||
### Help this is all too informal! | ||
[Help this is all too informal!]: #help-this-is-all-too-informal | ||
|
||
The process is intended to be as lightweight as reasonable for the | ||
present circumstances. As usual, we are trying to let the process be | ||
driven by consensus and community norms, not impose more structure than | ||
The process is intended to be as lightweight as reasonable for the | ||
present circumstances. As usual, we are trying to let the process be | ||
driven by consensus and community norms, not impose more structure than | ||
necessary. | ||
|
||
[core team]: https://github.com/mozilla/rust/wiki/Note-core-team | ||
[sub-team]: http://www.rust-lang.org/team.html |
Oops, something went wrong.