From 6e9ccd3f4398e13b9d9bf9e0581819b673795a36 Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Mon, 1 Dec 2008 12:54:16 +0000
Subject: [PATCH] better checking of case where a local name is used before it
 is defined (in an int-def context)

svn: r12659
---
 collects/scheme/private/class-internal.ss | 14 ++++++++++++++
 collects/scheme/private/classidmap.ss     | 12 +++++++-----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/collects/scheme/private/class-internal.ss b/collects/scheme/private/class-internal.ss
index 37006a569d..d98c6625bf 100644
--- a/collects/scheme/private/class-internal.ss
+++ b/collects/scheme/private/class-internal.ss
@@ -173,6 +173,20 @@
     [super-instantiate super-instantiate-param]
     [super-new super-new-param])
 
+  ;;--------------------------------------------------------------------
+  ;;  local member name lookup
+  ;;--------------------------------------------------------------------
+
+  (define-for-syntax (localize orig-id)
+    (do-localize orig-id #'validate-local-member))
+
+  (define (validate-local-member orig s)
+    (if (symbol? s)
+        s
+        (error 'local-member-name
+               "used before its definition: ~a"
+               orig)))
+
   ;;--------------------------------------------------------------------
   ;;  class macros
   ;;--------------------------------------------------------------------
diff --git a/collects/scheme/private/classidmap.ss b/collects/scheme/private/classidmap.ss
index f46886cf2f..b88fb8b098 100644
--- a/collects/scheme/private/classidmap.ss
+++ b/collects/scheme/private/classidmap.ss
@@ -293,15 +293,17 @@
 
   (define-struct private-name (orig-id gen-id))
 
-  (define (localize orig-id)
+  (define (do-localize orig-id validate-local-member-stx)
     (let loop ([id orig-id])
       (let ([v (syntax-local-value id (lambda () #f))])
 	(cond
 	 [(and v (private-name? v))
 	  (list 'unquote 
-		(binding (private-name-orig-id v)
-			 id
-			 (private-name-gen-id v)))]
+                (list validate-local-member-stx
+                      (list 'quote orig-id)
+                      (binding (private-name-orig-id v)
+                               id
+                               (private-name-gen-id v))))]
 	 [(and (set!-transformer? v)
 	       (s!t? (set!-transformer-procedure v)))
 	  (s!t-ref (set!-transformer-procedure v) 1)]
@@ -353,6 +355,6 @@
                         make-init-error-map make-init-redirect super-error-map 
                         make-with-method-map
                         flatten-args make-method-call
-                        make-private-name localize
+                        do-localize make-private-name
                         generate-super-call generate-inner-call
                         generate-class-expand-context class-top-level-context?)))