fixing typing of find-variable

2011-03-11 14:02:06 -05:00 · 2011-03-11 14:02:06 -05:00 · b1ca4078b5
commit b1ca4078b5
parent 05d6043613
1 changed files with 9 additions and 9 deletions
--- a/lexical-env.rkt
+++ b/lexical-env.rkt
@ -49,8 +49,8 @@

 (: list-index (All (A) A (Listof A) -> (U #f Natural)))
 (define (list-index x l)
-  (let loop ([i 0]
-             [l l])
+  (let: loop : (U #f Natural) ([i : Natural 0]
+                               [l : (Listof A) l])
        (cond
          [(empty? l)
           #f]