racket / racket/typed-racket

Invariable-Arity Function

Open
#602 22 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Dominant language
Racket
Stars
575
Forks
106
Avg merge
2h 1m
Merged PRs (30d)
2

Description

What version of Racket are you using?

6.10.1

What program did you run?

#lang typed/racket
(: a (-> Number (List Number)))
(define (a . b)
b)

What should have happened?

I expected this to type check.

If you got an error message, please include it here.

Type Checker: type mismatch
expected: (List Number)
given: (Listof Any) in: b

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.

Research direction

Start with the provided #lang typed/racket reproduction and the variadic definition of a. Inspect how the type checker infers the type of b for an invariable-arity function. Done means the example type checks with b accepted as (List Number), with regression coverage for this behavior.

Written by the indexing model from the issue text.

Assessment

Domain
compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
30/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.