diff --git a/collects/teachpack/2htdp/scribblings/image-guide.scrbl b/collects/teachpack/2htdp/scribblings/image-guide.scrbl index bbf50ee664..2000dee343 100644 --- a/collects/teachpack/2htdp/scribblings/image-guide.scrbl +++ b/collects/teachpack/2htdp/scribblings/image-guide.scrbl @@ -164,10 +164,10 @@ and avoiding extra thick lines on the interior. For example, consider building a grid like this: @image-interaction[ -(define s (square 20 'outline 'black)) -(define r (beside s s s s s s)) -(define q (above r r r r r r)) -q +(define s1 (square 20 'outline 'black)) +(define r1 (beside s1 s1 s1 s1 s1 s1)) +(define q1 (above r1 r1 r1 r1 r1 r1)) +q1 ] The reason interior lines in this grid are the same thickness as the lines around the edge @@ -205,13 +205,13 @@ black pen, but we can crop out the outer portion of the pen. Using that we can build a grid now too, but this grid has doubled lines on the interior. -@image-interaction[(let* ([s (crop - 0 0 20 20 - (rectangle - 20 20 "outline" - (make-pen "black" 2 "solid" "round" "round")))] - [r (beside s s s s s s)]) - (above r r r r r r))] +@image-interaction[ +(define pn (make-pen "black" 2 "solid" "round" "round")) +(define s2 (crop 0 0 20 20 (rectangle 20 20 "outline" pn))) +(define r2 (beside s2 s2 s2 s2 s2 s2)) +(define q2 (above r2 r2 r2 r2 r2 r2)) +q2 +] While this kind of rectangle is not useful for building grids, it is important to be able to build rectangles whose drawing does not