Provide a more informative internal error

original commit: 04e8e33313842d94d0cbff458ad23047ee1441fc
2012-12-04 15:33:02 -05:00 · 2012-12-04 15:33:02 -05:00 · 3ff53eb009
commit 3ff53eb009
parent a0c32ff288
1 changed files with 7 additions and 1 deletions
--- a/collects/typed-racket/types/substitute.rkt
+++ b/collects/typed-racket/types/substitute.rkt
@ -48,7 +48,13 @@
                 [#:F name (hash-ref subst name target)]
                 [#:arr dom rng rest drest kws
                        (cond
-                          [(and (pair? drest) (ormap (and/c (cdr drest) (not/c bound-tvar?)) names)) =>
+                          [(and (pair? drest)
+                                (ormap (λ (name)
+                                          (and (equal? name (cdr drest))
+                                               (not (bound-tvar? name))
+                                               name))
+                                       names))
+                           =>
                           (lambda (name)
                             (int-err "substitute used on ... variable ~a in type ~a" name target))]
                          [else