Setting "type" to bright red to make comparison obvious:
(screenshots taken from VSCode)
Before
<img width="446" height="150" alt="Screenshot 2026-07-20 135558"
src="https://github.com/user-attachments/assets/81249005-99f1-47bb-af4f-ad6e8f2404fb"
/>
After
<img width="429" height="149" alt="Screenshot 2026-07-20 135738"
src="https://github.com/user-attachments/assets/acc83086-fe19-4a18-a833-968daed56229"
/>
I'm not super familiar with textmate/highlightjs, but I think what was
happening on line 5 is that the "type" scope is being extended to the
`=` after `.y`.
Adding `,` as an "end" token fixes this, and I think this is what
highlightjs already does.
I've also added "unused" as a keyword.
Implement the toolchain side of proposal #7254, removing the `:!`
binding
syntax for generic and template parameters in favor of the keywords
`generic`,
`template`, and `runtime` plus contextual defaults for phase.
For valid programs this is semantics-preserving: each binding resolves
to the
same phase, and produces the same SemIR, as it did under `:!`/`:`. The
parser
derives a binding's phase from its syntactic context plus any explicit
phase
keyword; new diagnostics and error recovery for misused keywords are
described
below.
Implementation details for each component:
- Lexer: remove the `:!` (`ColonExclaim`) token, move its virtual
parse-node
budget onto `:`, and add the `generic` and `runtime` keywords.
- Parser: thread a `BindingContext` (`ExplicitParam`, `DeducedParam`, or
`CompileTimeEntityParam`) from declaration introducers down through
parameter
lists to each binding pattern, using a one-token lookahead to
distinguish a
name-qualifier parameter list from a declaration's own final list.
Parameters
of a compile-time entity (`class`, `interface`, `constraint`, `choice`,
`alias`, `export`, `namespace`) and deduced `[]` parameters default to
checked
generic; explicit function parameters and local bindings default to
runtime.
`HandleBindingPattern` resolves the phase from that context plus the
keyword: a
`generic` keyword needs no node of its own (the phase is carried by the
binding's node kind), while a `runtime` keyword is preserved as a
`RuntimeBindingName` node so `check` can name it in a diagnostic. A
phase
keyword that is merely redundant with the contextual default is
diagnosed
here, without invalidating the parse tree.
- Check: a phase keyword that is invalid for its context (for example
`runtime`
on a checked-generic parameter) is diagnosed here, and recovers by
building an
error binding that still introduces the name so that later uses of it do
not
produce cascading errors.
The removed `:!` syntax is now rejected as an ordinary parse error.
The `form`/`:?`/`->?` ("extended types") portion of proposal #7254 is
left for a
separate change.
Assisted-by: Claude Code
TextMate doesn't support JSON grammars, so convert our JSON grammar to a
plist automatically as a pre-commit check. Fix malformed info.plist
file. Add missing uuid to grammar file.
Assisted-by: Gemini via Antigravity
Switch into C++ syntax highlighting mode inside inline C++ fragments in
Carbon code. Add a background to them to make their boundaries stand out
a bit more.
Assisted-by: Gemini via Antigravity
This PR improves the vscode syntax highlighting.
- Added `comment` keys.
- Added highlighting of invalid numbers such as `0x`, `0b`, `0xa`, etc.
- Restricted highlighting of numeric type literals to common types to
avoid highlighting identifiers such as `i1`.
- Changed the highlighting of named operators (e.g., `as`).
- Added `char` and `str` to type literals.
- Added `const` to modifier keywords.
- Removed `addr` keyword.
- Refactored some rules to use `begin`/`end` to handle line breaks.
- Added highlighting to `choice` values as `enum` values.
- Updated the rules for matching `types`.
- Added highlighting to rhs of `adapt`, `alias`, `choice`, `constraint`,
`impl`, `interface`, `as`, and `impls`.
- Added highlighting to rhs of bindings.
- Added highlighting to function return types.
- Updated the rules for matching `functions`.
- Updated the rules for matching `variables`.
- Added highlighting unidentified words as `variable`.
- Added examples and before/after screenshots.
| Before | After |
| :---: | :---: |
| <img width="424" alt="before"
src="https://github.com/user-attachments/assets/e84d0ff9-237b-40c2-845b-ec550b8f7bea">
| <img width="431" alt="now"
src="https://github.com/user-attachments/assets/2c18640b-318a-4cd5-952c-bad61d3fdbca">
|
---------
Co-authored-by: Dana Jansens <danakj@orodu.net>
Introduce a principle that the Carbon language should not encroach on
the
developer's namespace. Satisfy this principle by making `Core` a
keyword.
---------
Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
This is a modifier if it appears before an introducer and a control flow
keyword if it appears before `=>`. Use introducer highlighting if it's
neither.
VSCode's JSON parser no longer accepts comments in at least textmate
grammars, so remove the comments. It's unclear whether VSCode changed
here or whether this hasn't worked since the comments were added.
Clean up the textmate grammar: refactor, add some missing operators and
keywords, classify keywords as introducer / modifier as appropriate, fix
comment grammar to require space after `//`, and generalize recognition
of iN, fN, uN to recognize all such type literals.
Be more cautious in language server -- I was seeing frequent crashes for
`IdentifierName` parse nodes whose token was not actually an identifier,
presumably due to error recovery.
This PR adds filetype highlighting support to block string literals in
the TextMate grammar.
After adding the regex in the `begin` of the block string literal,
`beginCaptures` is used to access the first capturing group of the regex
(which captures the filetype) and apply the `constant.character.escape`
rule.
Closes#3641
Also make minor updates to the skeletal design in
docs/design/name_lookup.md following #2113, as there are no longer any prelude names that are made available to unqualified name lookup by default.
Add `type` to the keyword list in
docs/design/lexical_conventions/words.md, following #2360.
codespell now sees "falsy" as a mis-spelling of either "false" or "falsely"; adding it since I think this it's occasionally used this way in programming. e.g., https://developer.mozilla.org/en-US/docs/Glossary/Falsy
Adjusts to use the new check-copyright support for lines starting with a dash.
TextMate is the go-to definition language for syntax highlighting for editors lack dedicated language support for a given programming language. This patch contains a very minimal, yet functional TextMate bundle definition for Carbon.
This allows Carbon users to import the TextMate bundle into their editors to get basic syntax highlighting for Carbon code until we have a more solid specification for the language (that's when the fun with dedicated plugins/extensions begins!).
**Support**
- String literals with escape codes (currently using C highlighting rules)
- Numeric literals in decimal, hexadecimal and binary (lacks _ separator support though)
- Single and multi-line comments
- Highlighting of all? (let me know if some are missing) keywords in the language
Here is an image of the highlighting in action in IntelliJ Dracula mode
oli-ej
Chandler Carruth
Richard Smith
ÖzgürandDana Jansens
Karthik Prakash
czapiga
Manmeet Singh
Jon Ross-Perkins
Mats Larsen
