diff --git a/beautiful-racket-demo/basic-demo/expander0.rkt b/beautiful-racket-demo/basic-demo/expander-runtime-errors.rkt
similarity index 100%
rename from beautiful-racket-demo/basic-demo/expander0.rkt
rename to beautiful-racket-demo/basic-demo/expander-runtime-errors.rkt
diff --git a/beautiful-racket-demo/basic-demo/expander.rkt b/beautiful-racket-demo/basic-demo/expander.rkt
index 745c9af..b436835 100644
--- a/beautiful-racket-demo/basic-demo/expander.rkt
+++ b/beautiful-racket-demo/basic-demo/expander.rkt
@@ -18,34 +18,34 @@
        (run line-table))))
 (provide (rename-out [b-module-begin #%module-begin]))
 
-(struct $program-end-signal ())
-(define (b-end) (raise ($program-end-signal)))
+(struct end-program-signal ())
+(struct change-line-signal (val))
 
-(struct $change-line-signal (val))
-(define (b-goto expr) (raise ($change-line-signal expr)))
+(define (b-end) (raise (end-program-signal)))
+(define (b-goto num-expr) (raise (change-line-signal num-expr)))
 
 (define (run line-table)
   (define line-vec
     (list->vector (sort (hash-keys line-table) <)))
-  (with-handlers ([$program-end-signal? void])
+  (with-handlers ([end-program-signal? (λ (exn-val) (void))])
     (for/fold ([line-idx 0])
-              ([i (in-naturals)])
-      (unless (< line-idx (vector-length line-vec)) (b-end))
+              ([i (in-naturals)]
+               #:break (>= line-idx (vector-length line-vec)))
       (define line-num (vector-ref line-vec line-idx))
-      (define line-proc (hash-ref line-table line-num))
+      (define line-func (hash-ref line-table line-num))
       (with-handlers
-          ([$change-line-signal?
+          ([change-line-signal?
             (λ (cls)
-              (define clsv ($change-line-signal-val cls))
+              (define clsv (change-line-signal-val cls))
               (or
                (and (exact-positive-integer? clsv)
                     (vector-member clsv line-vec))
                (error (format "error in line ~a: line ~a not found"
                               line-num clsv))))])
-        (line-proc)
+        (line-func)
         (add1 line-idx)))))
 
-(define b-rem void)
+(define (b-rem val) (void))
 (define (b-print [val ""]) (displayln val))
 (define (b-sum . nums) (apply + nums))
 (define (b-num-expr expr)
diff --git a/beautiful-racket-demo/basic-demo/info.rkt b/beautiful-racket-demo/basic-demo/info.rkt
new file mode 100644
index 0000000..9641805
--- /dev/null
+++ b/beautiful-racket-demo/basic-demo/info.rkt
@@ -0,0 +1,4 @@
+#lang info
+
+(define compile-omit-paths 'all)
+(define test-omit-paths 'all)
\ No newline at end of file