internal error type-checking a dot type program

[mfelleisen]

What version of Racket are you using?

6.8.0.2--2017-02-10

What program did you run?

#lang typed/racket

(define-type Filter
  (All (a b ...) (-> (-> a b ... b Any) (Listof a) (Listof b) ... (Listof a))))

(: filter* Filter)
(define (filter* p? l)
  (cond
    [(andmap empty? l) '[]]
    [else (define fst ({inst map a b ...} first l))
          (define rst (apply filter* p? ({inst map a b ...} rest l)))
          (if (apply p? fst) (cons fst rst) rst)]))

(filter* (lambda ({x : Integer}) (> x 1)) '(0 1 2))

What should have happened?

type error

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

plt/racket/share/pkgs/typed-racket-lib/typed-racket/utils/tc-utils.rkt:271:0: Internal Typechecker Error: Got non-dcons: #(struct:dcon-dotted () #(struct:c Nothing b) b) #(struct:dcon-exact () #(struct:c Nothing Any))
while typechecking:
(#%app apply filter* p? (#%app (#%expression map) rest l))
originally:
(apply filter* p? ((inst map a b ...) rest l))