Index: doc/example-scripts/tk-horse-race.tcl
===================================================================
diff -u -N -r2076ef459f42cdf6426522aab56be490b66c2436 -r6ad7855cd7aba089f7a160293802e1639d0d6198
--- doc/example-scripts/tk-horse-race.tcl	(.../tk-horse-race.tcl)	(revision 2076ef459f42cdf6426522aab56be490b66c2436)
+++ doc/example-scripts/tk-horse-race.tcl	(.../tk-horse-race.tcl)	(revision 6ad7855cd7aba089f7a160293802e1639d0d6198)
@@ -41,8 +41,8 @@
    :property canvas:required    ;# the canvas, on which the horse is drawn
    :property n:integer,required ;# the position on the canvas
    
-   :useTrait nx::TCallback
-   :useTrait TListUtils
+   :require trait nx::TCallback
+   :require trait TListUtils
    
    :method draw {x y} {
      set hide [:lpick {black brown white gray brown3 brown4}]
@@ -80,8 +80,8 @@
    :property {height 330}   ;# height of the canvas
    :property {horses}       ;# a list of horse names participating in the game
    
-   :useTrait nx::TCallback
-   :useTrait TListUtils
+   :require trait nx::TCallback
+   :require trait TListUtils
    
    :method init {} {
      #