+static int set_children(const tal_t *parent, char val)
+{
+ char *iter;
+ int num = 0;
+
+ for (iter = tal_first(parent); iter; iter = tal_next(iter)) {
+ ok1(*iter == '0');
+ *iter = val;
+ num++;
+ num += set_children(iter, val);
+ }
+ return num;
+}
+
+static void check_children(const tal_t *parent, char val)
+{
+ const char *iter;
+
+ for (iter = tal_first(parent); iter; iter = tal_next(iter)) {
+ ok1(*iter == val);
+ check_children(iter, val);
+ }
+}
+