gistfile1.txt

diff --git a/ext/peg/peg.scm b/ext/peg/peg.scm
index dec9d65..dd968d8 100644
--- a/ext/peg/peg.scm
+++ b/ext/peg/peg.scm
@@ -246,12 +246,13 @@
 (define (peg-parser->generator parser src)
   (let1 s (%->lseq src)
     (generate (^[yield]
-                (let loop ([s s])
+                (let loop ()
                   (receive (r v s1) (parser s)
                     (if (parse-success? r)
                       (unless (eof-object? v)
                         (yield (rope-finalize v))
-                        (loop s1))
+                        (set! s s1)
+                        (loop))
                       (raise (construct-peg-parser-error r v s s1)))))))))
 
 ;;;============================================================