microsoft / microsoft/TypeScript
Generic syntax ambiguity is handled incorrectly
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Nobody has claimed this yet.
Bug
Domain: Parser
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Description
🔎 Search Terms
generic syntax ambiguity
🕗 Version & Regression Information
- I was unable to test this on prior versions because there is no online tooling for it
⏯ Playground Link
💻 Code
const a = 1, b = 2, c = 3, d = 4, e = 5;
console.log(a < b, (c > (d & e)));
🙁 Actual behavior
This expression is not callable.
🙂 Expected behavior
true false
Additional information about the issue
While there might be some justification for why
const a = 1, b = 2, c = 3, d = 4, e = 5;
console.log(a < b, c > (d & e));
doesn't work as it did in JS, in the provided example there isn't even any disambiguity.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Reproduce the reported expression in the linked TypeScript Playground and compare it with the version without parentheses. Trace the compiler's handling of generic syntax ambiguity for this expression; done means the provided code is accepted and produces true false without regressing the related ambiguous form.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- javascript, typescript
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100