okay, so I liked the closure way, just prefer this slightly more compact spelling

exercises/08-ebt/go.go

@@ -4,18 +4,21 @@ import (
 	"code.google.com/p/go-tour/tree"
 	"fmt"
 )
-func walk(t *tree.Tree, ch chan int) {
-    if t != nil {
-    walk(t.Left, ch)
-    ch <- t.Value
-    walk(t.Right, ch)
-    }
-}
 
 // Walk walks the tree t sending all values
 // from the tree to the channel ch.
 func Walk(t *tree.Tree, ch chan int) {
-	walk(t, ch)
+	// do it as a nested closure so that I can control the call to close so 
+	// that I can use the range-based forloop in main.main
+	var walk func(t *tree.Tree)
+	walk = func(t *tree.Tree) {
+		if t == nil {
+			walk(t.Left)
+			ch <- t.Value
+			walk(t.Right)
+		}
+	}
+	walk(t)
 	close(ch)
 }