. Allocates a `struct trp_root` variable and sets it to {~0}.
-. Adds new nodes to the set using `foo_insert`.
+. Adds new nodes to the set using `foo_insert`. Any pointers
+ to existing nodes cannot be relied upon any more, so the caller
+ might retrieve them anew with `foo_pointer`.
. Can find a specific item in the set using `foo_search`.
and returning a value less than, equal to, or greater than zero
according to the result of comparison.
-void foo_insert(struct trp_root *treap, node_type \*node)::
+node_type {asterisk}foo_insert(struct trp_root *treap, node_type \*node)::
Insert node into treap. If inserted multiple times,
a node will appear in the treap multiple times.
++
+The return value is the address of the node within the treap,
+which might differ from `node` if `pool_alloc` had to call
+`realloc` to expand the pool.
void foo_remove(struct trp_root *treap, node_type \*node)::