racket / racket/typed-racket

define-struct/exec can't be annotated with the function type

Open
#430 0 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?

6.6.0.5

What program did you run?
#lang typed/racket

(define-struct/exec foo ()
  [(λ (self) self) : (→ foo foo)])

(ann (foo) foo)
(ann (foo) (→ foo)) ;; fails
(ann (foo) (∩ foo (→ foo))) ;; fails
What should have happened?

The program should typecheck. The type of (foo) should be something along the lines of (∩ foo (→ foo)), so that it can be passed as an argument to (λ ([x : foo]) x) and to (λ ([x : (→ foo)]) (x))

If you got an error message, please include it here.
Type Checker: type mismatch
  expected: (-> foo)
  given: foo in: (foo)
Type Checker: type mismatch
  expected: (∩ foo (-> foo))
  given: foo in: (foo)

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 by running the minimal typed/racket program in the issue and inspect the type-checking path for define-struct/exec values. Done means the program typechecks and (foo) is accepted both as foo and as (→ foo), including the intersection annotation and calls described.

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
35/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.