From c390d9678072cbd5a4ff46dfff7aa736216a1ea5 Mon Sep 17 00:00:00 2001
From: Jon Rafkind <rafkind@racket-lang.org>
Date: Thu, 12 Apr 2012 12:48:59 -0600
Subject: [PATCH] [honu] only allow semicolons in expression sequence position

---
 collects/honu/core/private/honu-typed-scheme.rkt | 7 +++++++
 collects/honu/core/private/parse2.rkt            | 5 ++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/collects/honu/core/private/honu-typed-scheme.rkt b/collects/honu/core/private/honu-typed-scheme.rkt
index 4c4e9db509..edd082899a 100644
--- a/collects/honu/core/private/honu-typed-scheme.rkt
+++ b/collects/honu/core/private/honu-typed-scheme.rkt
@@ -472,9 +472,16 @@ Then, in the pattern above for 'if', 'then' would be bound to the following synt
      (debug "expanded ~a unexpanded ~a\n"
             (if parsed (syntax->datum parsed) parsed)
             (syntax->datum unparsed))
+     #'(begin
+         (define-syntax (parse-more stx)
+           (syntax-case stx ()
+             [(_ stuff (... ...))
+              (do-parse-rest #'(stuff (... ...)) #'parse-more)]))
+         (parse-more forms ...))
      ;; if parsed is #f then we don't want to expand to anything that will print
      ;; so use an empty form, begin, `parsed' could be #f becuase there was no expression
      ;; in the input such as parsing just ";".
+     #;
      (with-syntax ([parsed (if (not parsed) #'(begin)
                              (remove-repeats parsed)
                              #;
diff --git a/collects/honu/core/private/parse2.rkt b/collects/honu/core/private/parse2.rkt
index a1cb598477..53ee99c947 100644
--- a/collects/honu/core/private/parse2.rkt
+++ b/collects/honu/core/private/parse2.rkt
@@ -143,7 +143,9 @@
 
 (provide do-parse-rest)
 (define (do-parse-rest stx parse-more)
-  (syntax-parse stx
+  (syntax-parse stx #:literal-sets (cruft)
+    [(semicolon semicolon ... rest ...)
+     (do-parse-rest #'(rest ...) parse-more)]
     [(stuff ...)
      (debug "Parse rest ~a\n" (syntax->datum #'(stuff ...)))
      (define-values (parsed unparsed)
@@ -431,6 +433,7 @@
            (define-splicing-syntax-class no-left
              [pattern (~seq) #:when (and (= precedence 0) (not current))])
            (syntax-parse #'(head rest ...) #:literal-sets (cruft)
+             #;
              [(semicolon . rest)
               (debug "Parsed a semicolon, finishing up with ~a\n" current)
               (values (left current) #'rest)]