Tracking Issue for frontmatter

[epage]

This is a tracking issue for the RFC "frontmatter" (rust-lang/rfcs#3503).
The feature gate for the issue is #![feature(frontmatter)].

About tracking issues

Tracking issues are used to record the overall progress of implementation.
They are also used as hubs connecting to other relevant issues, e.g., bugs or open design questions.
A tracking issue is however not meant for large scale discussion, questions, or bug reports about a feature.
Instead, open a dedicated issue for the specific matter and add the relevant feature gate label.
Discussion comments will get marked as off-topic or deleted.
Repeated discussions on the tracking issue may lead to the tracking issue getting locked.

Steps

• Implement the RFC for rustc (Add unstable frontmatter support #137193)
• Implement the RFC for r-a
• Adjust documentation (see instructions on rustc-dev-guide)
• Formatting for new syntax has been added to the Style Guide (nightly-style-procedure)
• Stabilization PR (see instructions on rustc-dev-guide)

Unresolved Questions

• What level of quality of error messages is a blocker for stabilization? See also Add unstable frontmatter support #137193 (comment)

Implementation history

[epage]

Support in external parsers

• feature: frontmatter syntax support tree-sitter/tree-sitter-rust#253
• [Rust] Frontmatter syntax support sublimehq/Packages#4164
• Support Rust's frontmatter syntax in rust.vim rust.vim#522 (Support Rust's frontmatter syntax in rust.vim neovim/neovim#32534)
• Support Rust's frontmatter syntax dustypomerleau/rust-syntax#50 (used by VS Code)