From 5b57736af6e227edbf87021be3abe026caccd6ea Mon Sep 17 00:00:00 2001 From: Vincent St-Amour Date: Tue, 3 Nov 2015 14:32:23 -0600 Subject: [PATCH] Guard some unsafe ops. --- typed-racket-lib/typed-racket/types/current-seen.rkt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/typed-racket-lib/typed-racket/types/current-seen.rkt b/typed-racket-lib/typed-racket/types/current-seen.rkt index 33baac42..ed92b27c 100644 --- a/typed-racket-lib/typed-racket/types/current-seen.rkt +++ b/typed-racket-lib/typed-racket/types/current-seen.rkt @@ -24,5 +24,5 @@ A)) (define (seen? ss st cs) (for/or ([i (in-list cs)]) - (and (eq? ss (unsafe-car i)) (eq? st (unsafe-cdr i))))) + (and (pair? i) (eq? ss (unsafe-car i)) (eq? st (unsafe-cdr i)))))