typed-racket

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What version of Racket are you using?

Racket 7.7-1

What program did you run?

#lang typed/racket
(match '(cond [#t a b c]
              [#f x y z])
  [`(cond [,(? boolean? #{preds : (Listof Boolean)})
           ,(? symbol?  #{bodys : (Listof (Listof Symbol))})
           ...]
          ...)
   bodys])

What should have happened?

In racket:

#lang racket
(match '(cond [#t a b c]
              [#f x y z])
  [`(cond [,(? boolean? preds)
           ,(? symbol?  bodys)
           ...]
          ...)
   bodys])

Output is:

'((a b c) (x y z))

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

In typed/racket, it failed:

Type Checker: type mismatch
  expected: (U (List 'a 'b 'c) (List 'x 'y 'z))
  given: (U (List 'b 'c) (List 'y 'z))
  in: (match (quote (cond (#t a b c) (#f x y z))) ((quasiquote (cond ((unquote (? boolean? preds)) (unquote (? symbol? bodys)) ...) ...)) bodys))

What version of Racket are you using?

8.0

What program did you run?

#lang typed/racket

(: ls (Pair Number (Listof Number)))
(define ls '(0 1 2 3 4))

(match ls
  [`(,(? number? #{nums : (Pair Number (Listof Number))}) ..1)
   (displayln nums)])

What should have happened?

Output:

(0 1 2 3 4)

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

Type Checker: type mismatch
  expected: (Pairof Number (Listof Number))
  given: Null
  in: (match ls ((quasiquote ((unquote (? number? nums)) ..1)) (displayln nums)))