diff --git a/examples/square_maze.scad b/examples/square_maze.scad
index 6bb92f82..3a65f171 100644
--- a/examples/square_maze.scad
+++ b/examples/square_maze.scad
@@ -198,23 +198,23 @@ function try_routes_from(x, y, dir, maze, rows, columns, x_circular, y_circular)
         : maze;   
 
 
-module draw_block(wall_type, block_width, wall_thickness) {
-    if(wall_type == UPPER_WALL || wall_type == UPPER_RIGHT_WALL) {
-        // draw a upper wall
-        line2d(
-            [0, block_width], [block_width, block_width], wall_thickness
-        ); 
+module draw_maze(rows, columns, blocks, block_width, wall_thickness, x_circular = false, y_circular = false) {
+    module draw_block(wall_type, block_width, wall_thickness) {
+        if(wall_type == UPPER_WALL || wall_type == UPPER_RIGHT_WALL) {
+            // draw a upper wall
+            line2d(
+                [0, block_width], [block_width, block_width], wall_thickness
+            ); 
+        }
+        
+        if(wall_type == RIGHT_WALL || wall_type == UPPER_RIGHT_WALL) {
+            // draw a right wall
+            line2d(
+                [block_width, block_width], [block_width, 0], wall_thickness
+            ); 
+        }
     }
     
-    if(wall_type == RIGHT_WALL || wall_type == UPPER_RIGHT_WALL) {
-        // draw a right wall
-        line2d(
-            [block_width, block_width], [block_width, 0], wall_thickness
-        ); 
-    }
-}
-
-module draw_maze(rows, columns, blocks, block_width, wall_thickness, x_circular = false, y_circular = false) {
     for(block = blocks) {
         // move a block to a right position.
         translate([get_x(block) - 1, get_y(block) - 1] * block_width)