From bae79dda0bbbcb87ca0cf5db2d11b6de6e6a88a4 Mon Sep 17 00:00:00 2001
From: Robby Findler <robby@racket-lang.org>
Date: Tue, 25 May 2010 17:26:10 -0500
Subject: [PATCH] closes PR 10930

---
 collects/teachpack/2htdp/scribblings/image-gen.rkt |  2 +-
 collects/teachpack/2htdp/scribblings/image-toc.rkt |  2 ++
 collects/teachpack/2htdp/scribblings/image.scrbl   | 10 ++++++----
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/collects/teachpack/2htdp/scribblings/image-gen.rkt b/collects/teachpack/2htdp/scribblings/image-gen.rkt
index 36b5fd00bb..e3a7b65170 100644
--- a/collects/teachpack/2htdp/scribblings/image-gen.rkt
+++ b/collects/teachpack/2htdp/scribblings/image-gen.rkt
@@ -103,7 +103,7 @@
    (printf "image-gen: didn't find any images; probably this means that you need to delete .zo files and try again\n")]
   [else
    (printf "\n")
-   (call-with-output-file "image-toc.ss"
+   (call-with-output-file "image-toc.rkt"
      (λ (port)
        (fprintf port "#lang scheme/base\n(provide mapping)\n")
        (fprintf port ";; this file is generated by image-gen.ss -- do not edit\n;; note that the file that creates this file depends on this file\n;; it is always safe to simply define (and provide) mapping as the empty list\n\n")
diff --git a/collects/teachpack/2htdp/scribblings/image-toc.rkt b/collects/teachpack/2htdp/scribblings/image-toc.rkt
index 3813f89609..17c067ad53 100644
--- a/collects/teachpack/2htdp/scribblings/image-toc.rkt
+++ b/collects/teachpack/2htdp/scribblings/image-toc.rkt
@@ -10,6 +10,7 @@
    (list '(image-baseline (rectangle 100 100 "solid" "black")) 'val 100)
    (list '(image-height (text "Hello" 24 "black")) 'val 24)
    (list '(image-baseline (text "Hello" 24 "black")) 'val 18)
+   (list '(image-height (rectangle 10 0 "solid" "purple")) 'val 0)
    (list
     '(image-height
       (overlay (circle 20 "solid" "orange") (circle 30 "solid" "purple")))
@@ -17,6 +18,7 @@
     60)
    (list '(image-height (circle 30 "solid" "orange")) 'val 60)
    (list '(image-height (ellipse 30 40 "solid" "orange")) 'val 40)
+   (list '(image-width (rectangle 0 10 "solid" "purple")) 'val 0)
    (list
     '(image-width
       (beside (circle 20 "solid" "orange") (circle 20 "solid" "purple")))
diff --git a/collects/teachpack/2htdp/scribblings/image.scrbl b/collects/teachpack/2htdp/scribblings/image.scrbl
index 4091da84f8..b677076ec4 100644
--- a/collects/teachpack/2htdp/scribblings/image.scrbl
+++ b/collects/teachpack/2htdp/scribblings/image.scrbl
@@ -848,22 +848,24 @@ the parts that fit onto @scheme[scene].
 
 @section{Image Properties}
 
-@defproc[(image-width [i image?]) (and/c integer? positive? exact?)]{
+@defproc[(image-width [i image?]) (and/c integer? (not/c negative?) exact?)]{
   Returns the width of @scheme[i].
                        
   @image-examples[(image-width (ellipse 30 40 "solid" "orange"))
                   (image-width (circle 30 "solid" "orange"))
                   (image-width (beside (circle 20 "solid" "orange")
-                                       (circle 20 "solid" "purple")))]
+                                       (circle 20 "solid" "purple")))
+                  (image-width (rectangle 0 10 "solid" "purple"))]
 }
 
-@defproc[(image-height [i image?]) (and/c integer? positive? exact?)]{
+@defproc[(image-height [i image?]) (and/c integer? (not/c negative?) exact?)]{
   Returns the height of @scheme[i].
   
   @image-examples[(image-height (ellipse 30 40 "solid" "orange"))
                   (image-height (circle 30 "solid" "orange"))
                   (image-height (overlay (circle 20 "solid" "orange")
-                                         (circle 30 "solid" "purple")))]
+                                         (circle 30 "solid" "purple")))
+                  (image-height (rectangle 10 0 "solid" "purple"))]
   }
 
 @defproc[(image-baseline [i image?]) (and/c integer? positive? exact?)]{