fix PR10810

svn: r18470 original commit: e703d52b945d51623a781dc97eda74a10430e1f9
2010-03-04 21:42:55 +00:00 · 2010-03-04 21:42:55 +00:00 · 3edcfaf5f5
commit 3edcfaf5f5
parent 04dbfaf38e
1 changed files with 3 additions and 0 deletions
--- a/collects/typed-scheme/private/colon.ss
+++ b/collects/typed-scheme/private/colon.ss
@ -39,6 +39,9 @@
  (define (err str . sub)
    (apply raise-syntax-error '|type declaration| str stx sub))  
  (syntax-parse stx*
+    [_ 
+     #:when (eq? 'expression (syntax-local-context))
+     (err "must be used in a definition context")]
    [(_ i:id ty)
     (syntax-property (internal (syntax/loc stx (:-internal i ty)))
                      'disappeared-use #'i)]