`struct`'s `#:methods` missing in Typed Racket

[Yi Cao]

What version of Racket are you using?

8.10

What program did you run?

In normal racket:

#lang racket/base

(require racket/generic)

(define-generics testable
  (test testable))
  
(struct myst (sth)
  #:methods gen:testable
  [(define (test self) (myst-sth self))])

(define x (myst "3648"))
(test x)  ;; => "3648"

However, in Typed Racket:

#lang typed/racket/base

(require racket/generic)

(define-generics testable
  (test testable))
  
(struct myst ([sth : Any])
  #:methods gen:testable
  [(define (test self) (myst-sth self))])

(define x (myst "3648"))
(test x)  ;; => ERROR: struct: expected one of these literals: #:mutable, #:transparent, #:prefab, #:constructor-name, #:extra-constructor-name, #:type-name, #:guard, or #:property

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

HelloWorld.rkt:8:0: struct: expected one of these literals: #:mutable, #:transparent, #:prefab, #:constructor-name, #:extra-constructor-name, #:type-name, #:guard, or #:property
  at: #:methods
  in: (struct myst ((sth : Any)) #:methods gen:testable ((define (test self) (myst-sth self))))
  parsing context: 
   while parsing typed structure type options
    term: (#:methods gen:testable ((define (test self) (m...
    location: <pkgs>/yacp/HelloWorld.rkt:8:0
  location...:
   HelloWorld.rkt:9:2
  context...:
   /Applications/Racket v8.10/collects/syntax/parse/private/runtime-report.rkt:739:0: error/report
   /Applications/Racket v8.10/collects/syntax/parse/private/runtime-report.rkt:25:0: call-current-failure-handler
   /Applications/Racket v8.10/share/pkgs/typed-racket-lib/typed-racket/tc-setup.rkt:71:0: tc-setup
   /Applications/Racket v8.10/share/pkgs/typed-racket-lib/typed-racket/typed-racket.rkt:22:4

[sorawee]

If I understand correctly, that's simply because it's not supported. The error message could be changed to indicate that it's not supported though.

[Yi Cao]

If I understand correctly, that's simply because it's not supported. The error message could be changed to indicate that it's not supported though.

If this is the case, when will this feature supported? 👀

[Sam Tobin-Hochstadt]

We do not have any timeline for that.