Hacktoberfest 2026: the issues maintainers tagged for October, open and beginner-friendly. Browse Hacktoberfest issues

TypeScript IntelliSense support less valid variable unicode identifier than tsc

Open
#915 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
typescript
Domain
tooling

Research direction

Reproduce the diagnostic in VS Code using the TypeScript TextMate grammar and the identifier shown in the issue, then inspect the grammar rule that recognizes variable identifiers. Done means the valid Unicode identifier is accepted without an Invalid character diagnostic while ordinary TypeScript identifiers continue to work.

Written by the indexing model from the issue text.

Description

Code

let let big𒊹f = 4;
console.log(big𒊹f);
//4

"𒊹" is a valid identifier unicode, in https://www.typescriptlang.org/play, it works normally.
But in vscode JavaScript and TypeScript Nightly extension, an error "Invalid character.ts(1127)" will show.

Dominant language
TypeScript
Stars
471
Forks
149
PR merge metrics
No merged PRs in 30d

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

More from microsoft/TypeScript-TmLanguage

All issues in microsoft/TypeScript-TmLanguage

Similar issues

More TypeScript issues

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.